Troubleshoot Azure File Sync cloud tiering

Cloud tiering, an optional feature of Azure File Sync, decreases the amount of local storage required while keeping the performance of an on-premises file server. When enabled, this feature stores only frequently accessed (hot) files on your local server. Infrequently accessed (cool) files are split into namespace (file and folder structure) and file content.

There are two paths for failures in cloud tiering:

  • Files can fail to tier, which means that Azure File Sync unsuccessfully attempts to tier a file to Azure Files.
  • Files can fail to recall, which means that the Azure File Sync file system filter (StorageSync.sys) fails to download data when a user attempts to access a file that has been tiered.

There are two main classes of failures that can happen via either failure path:

  • Cloud storage failures
    • Transient storage service availability issues. For more information, see the Service Level Agreement (SLA) for Azure Storage.
    • Inaccessible Azure file share. This failure typically happens when you delete the Azure file share when it is still a cloud endpoint in a sync group.
    • Inaccessible storage account. This failure typically happens when you delete the storage account while it still has an Azure file share that is a cloud endpoint in a sync group.
  • Server failures
    • Azure File Sync file system filter (StorageSync.sys) isn't loaded. In order to respond to tiering/recall requests, the Azure File Sync file system filter must be loaded. The filter not being loaded can happen for several reasons, but the most common reason is that an administrator unloaded it manually. The Azure File Sync file system filter must be loaded at all times for Azure File Sync to properly function.
    • Missing, corrupt, or otherwise broken reparse point. A reparse point is a special data structure on a file that consists of two parts:
      1. A reparse tag, which indicates to the operating system that the Azure File Sync file system filter (StorageSync.sys) might need to do some action on IO to the file.

      2. Reparse data, which indicates to the file system filter the URI of the file on the associated cloud endpoint (the Azure file share).

        The most common way a reparse point could become corrupted is if an administrator attempts to modify either the tag or its data.

    • Network connectivity issues. In order to tier or recall a file, the server must have internet connectivity.

The following sections indicate how to troubleshoot cloud tiering issues and determine if an issue is a cloud storage issue or a server issue.

How to monitor tiering activity on a server

To monitor tiering activity on a server, use Event ID 9003, 9016, and 9029 in the Telemetry event log (located under Applications and Services\Microsoft\FileSync\Agent in Event Viewer).

  • Event ID 9003 provides error distribution for a server endpoint. For example, Total Error Count and ErrorCode. Note, one event is logged per error code per hour.
  • Event ID 9016 provides ghosting results for a volume. For example, Free space percent is, Number of files ghosted in session, and Number of files failed to ghost.
  • Event ID 9029 provides ghosting session information for a server endpoint. For example, Number of files attempted in the session, Number of files tiered in the session, and Number of files already tiered.

How to monitor recall activity on a server

To monitor recall activity on a server, use Event ID 9005, 9006, 9009, and 9059 in the Telemetry event log (located under Applications and Services\Microsoft\FileSync\Agent in Event Viewer).

  • Event ID 9005 provides recall reliability for a server endpoint. For example, Total unique files accessed and Total unique files with failed access.
  • Event ID 9006 provides recall error distribution for a server endpoint. For example, Total Failed Requests and ErrorCode. Note, one event is logged per error code per hour.
  • Event ID 9009 provides recall session information for a server endpoint. For example, DurationSeconds, CountFilesRecallSucceeded, and CountFilesRecallFailed.
  • Event ID 9059 provides application recall distribution for a server endpoint. For example, ShareId, Application Name, and TotalEgressNetworkBytes.

How to identify files that are recalled on a server

  1. In Event Viewer, go to the Microsoft-FileSync-Agent/RecallResults event log.
  2. There is an event logged for each file that is recalled. If the DataTransferHresult field is 0, the file recall is successful. If the DataTransferHresult field has an error code, check the Recall errors and remediation section to see if remediation steps are listed for the error code.

How to troubleshoot files that fail to tier

To troubleshoot files that fail to tier, follow the steps:

  1. In Event Viewer, go to the Microsoft-FileSync-Agent/TieringResults event log.

  2. There is an event logged for each file that fails to tier. Check the Tiering errors and remediation section to see if remediation steps are listed for the error code.

    You can also use PowerShell to view the events that are logged to the TieringResults event log:

    Import-Module "C:\Program Files\Azure\StorageSyncAgent\StorageSync.Management.ServerCmdlets.dll"
    Get-StorageSyncFileTieringResult
    

If content doesn't exist for the error code, follow the general troubleshooting steps:

  1. Verify the file exists in the Azure file share.

    Note

    A file must be synced to an Azure file share before it can be tiered.

  2. Verify the server has Internet connectivity.

  3. Verify the Azure File Sync filter drivers (StorageSync.sys and StorageSyncGuard.sys) are running:

    • At an elevated command prompt, run fltmc. Verify that the StorageSync.sys and StorageSyncGuard.sys file system filter drivers are listed.

Note

If the server has a lot of tiering activities, some errors may be missing from the TieringResults event log due to wrapping. To prevent this issue, go to Event Viewer and increase the TieringResults event log size.

Tiering errors and remediation

HRESULT HRESULT (decimal) Error string Issue Remediation
0x80c86045 -2134351803 ECS_E_INITIAL_UPLOAD_PENDING The file failed to tier because the initial upload is in progress. No action required. The file will be tiered once the initial upload completes.
0x80c86043 -2134351805 ECS_E_GHOSTING_FILE_IN_USE The file failed to tier because it's in use. No action required. The file will be tiered when it's no longer in use.
0x80c80241 -2134375871 ECS_E_GHOSTING_EXCLUDED_BY_SYNC The file failed to tier because it's excluded by sync. No action required. Files in the sync exclusion list can't be tiered.
0x80c86042 -2134351806 ECS_E_GHOSTING_FILE_NOT_FOUND The file failed to tier because it wasn't found on the server. No action required. If the error persists, check if the file exists on the server.
0x80c83053 -2134364077 ECS_E_CREATE_SV_FILE_DELETED The file failed to tier because it was deleted in the Azure file share. No action required. The file should be deleted on the server when the next download sync session runs.
0x80c8600e -2134351858 ECS_E_AZURE_SERVER_BUSY The file failed to tier due to a network issue. No action required. If the error persists, check network connectivity to the Azure file share.
0x80072ee7 -2147012889 WININET_E_NAME_NOT_RESOLVED The file failed to tier due to a network issue. No action required. If the error persists, check network connectivity to the Azure file share.
0x80070005 -2147024891 ERROR_ACCESS_DENIED The file failed to tier due to access denied error. This error can occur if the file is located on a DFS-R read-only replication folder. Azure File Sync doesn't support server endpoints in DFS-R read-only replication folders. See planning guide for more information.
0x80072efe -2147012866 WININET_E_CONNECTION_ABORTED The file failed to tier due to a network issue. No action required. If the error persists, check network connectivity to the Azure file share.
0x80c80261 -2134375839 ECS_E_GHOSTING_MIN_FILE_SIZE The file failed to tier because the file size is less than the supported size. The minimum supported file size is based on the file system cluster size (double file system cluster size). For example, if the file system cluster size is 4 KiB, the minimum file size is 8 KiB.
0x80c83007 -2134364153 ECS_E_STORAGE_ERROR The file failed to tier due to an Azure storage issue. If the error persists, open a support request.
0x800703e3 -2147023901 ERROR_OPERATION_ABORTED The file failed to tier because it was recalled at the same time. No action required. The file will be tiered when the recall completes and the file is no longer in use.
0x80c80264 -2134375836 ECS_E_GHOSTING_FILE_NOT_SYNCED The file failed to tier because it hasn't synced to the Azure file share. No action required. The file will tier once it has synced to the Azure file share.
0x80070001 -2147942401 ERROR_INVALID_FUNCTION The file failed to tier because the cloud tiering filter driver (storagesync.sys) isn't running. To resolve this issue, open an elevated command prompt and run the following command: fltmc load storagesync
If the Azure File Sync filter driver fails to load when running the fltmc command, uninstall the Azure File Sync agent, restart the server, and reinstall the Azure File Sync agent.
0x80070070 -2147024784 ERROR_DISK_FULL The file failed to tier due to insufficient disk space on the volume where the server endpoint is located. To resolve this issue, free at least 100 MiB of disk space on the volume where the server endpoint is located.
0x80070490 -2147023728 ERROR_NOT_FOUND The file failed to tier because it hasn't synced to the Azure file share. No action required. The file will tier once it has synced to the Azure file share.
0x80c80262 -2134375838 ECS_E_GHOSTING_UNSUPPORTED_RP The file failed to tier because it's an unsupported reparse point. If the file is a Data Deduplication reparse point, follow the steps in the planning guide to enable Data Deduplication support. Files with reparse points other than Data Deduplication aren't supported and won't be tiered.
0x80c83052 -2134364078 ECS_E_CREATE_SV_STREAM_ID_
MISMATCH
The file failed to tier because it has been modified. No action required. The file will tier once the modified file has synced to the Azure file share.
0x80c80269 -2134375831 ECS_E_GHOSTING_REPLICA_NOT_
FOUND
The file failed to tier because it hasn't synced to the Azure file share. No action required. The file will tier once it has synced to the Azure file share.
0x80072ee2 -2147012894 WININET_E_TIMEOUT The file failed to tier due to a network issue. No action required. If the error persists, check network connectivity to the Azure file share.
0x80c80017 -2134376425 ECS_E_SYNC_OPLOCK_BROKEN The file failed to tier because it has been modified. No action required. The file will tier once the modified file has synced to the Azure file share.
0x800705aa -2147023446 ERROR_NO_SYSTEM_RESOURCES The file failed to tier due to insufficient system resources. If the error persists, investigate which application or kernel-mode driver is exhausting system resources.
0x8e5e03fe -1906441218 JET_errDiskIO The file failed to tier due to an I/O error when writing to the cloud tiering database. If the error persists, run chkdsk on the volume and check the storage hardware.
0x8e5e0442 -1906441150 JET_errInstanceUnavailable The file failed to tier because the cloud tiering database isn't running. To resolve this issue, restart the FileSyncSvc service or server. If the error persists, run chkdsk on the volume and check the storage hardware.
0x80C80285 -2134375803 ECS_E_GHOSTING_SKIPPED_BY_
CUSTOM_EXCLUSION_LIST
The file can't be tiered because the file type is excluded from tiering. To tier files with this file type, modify the GhostingExclusionList registry setting in HKEY_LOCAL_MACHINE
\SOFTWARE\Microsoft\Azure\StorageSync
0x80C86050 -2134351792 ECS_E_REPLICA_NOT_READY_FOR_
TIERING
The file failed to tier because the current sync mode is initial upload or reconciliation. No action required. The file will be tiered once sync completes initial upload or reconciliation.
0x80c8304e -2134364082 ECS_E_WORK_FRAMEWORK_ACTION_
RETRY_NOT_SUPPORTED
An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80c8309c -2134364004 ECS_E_CREATE_SV_BATCHED_CHANGE_
DETECTION_FAILED
An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x8000ffff -2147418113 E_UNEXPECTED An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80c80220 -2134375904 ECS_E_SYNC_METADATA_IO_ERROR The sync database has encountered an IO error. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80c830a7 -2134363993 ECS_E_AZURE_FILE_SNAPSHOT_LIMIT_
REACHED
The Azure file snapshot limit has been reached. Upgrade the Azure File Sync agent to the latest version. After upgrading the agent, run the DeepScrubbingScheduledTask located under \Microsoft\StorageSync.
0x80c80367 -2134375577 ECS_E_FILE_SNAPSHOT_OPERATION_
EXECUTION_MAX_ATTEMPTS_REACHED
An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80c8306f -2134364049 ECS_E_ETAG_MISMATCH An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80c8304c -2134364084 ECS_E_ASYNC_POLLING_TIMEOUT Timeout error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80070299 -2147024231 ERROR_FILE_SYSTEM_LIMITATION An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80c83054 -2134364076 ECS_E_CREATE_SV_UNKNOWN_
GLOBAL_ID
An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80c8309b -2134364005 ECS_E_CREATE_SV_PER_ITEM_CHANGE_
DETECTION_FAILED
An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80c83034 -2134364108 ECS_E_FORBIDDEN Access is denied. Please check the access policies on the storage account, and also check your proxy settings. Learn more.
0x80070034 -2147024844 ERROR_DUP_NAME An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80071128 -2147020504 ERROR_INVALID_REPARSE_DATA The data is corrupted and unreadable. Run chkdsk on the volume. Learn more.
0x8e5e0450 -1906441136 JET_errInvalidSesid An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80092004 -2146885628 CRYPT_E_NOT_FOUND Certificate required for Azure File Sync authentication is missing. Run this PowerShell command on the server to reset the certificate:
Reset-AzStorageSyncServerCertificate -ResourceGroupName <string> -StorageSyncServiceName <string>.
0x80c80020 -2134376416 ECS_E_CLUSTER_NOT_RUNNING The Failover Cluster service is not running. Verify the cluster service (clussvc) is running. Learn more.
0x80c83036 -2134364106 ECS_E_NOT_FOUND An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x801f0005 -2145452027 ERROR_FLT_INVALID_NAME_REQUEST An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80071126 -2147020506 ERROR_NOT_A_REPARSE_POINT An internal error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80070718 -2147023080 ERROR_NOT_ENOUGH_QUOTA Not enough server memory resources available to process this command. Monitor memory usage on your server. Learn more.
0x8007046a -2147023766 ERROR_NOT_ENOUGH_SERVER_
MEMORY
Not enough server memory resources available to process this command. Monitor memory usage on your server. Learn more.
0x80070026 -2147024858 COR_E_ENDOFSTREAM An external error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80131501 -2146233087 COR_E_SYSTEM An external error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80c86040 -2134351808 ECS_E_AZURE_FILE_SHARE_INVALID_
HEADER
An unexpected error occurred. If the error persists for more than a day, create a support request.
0x80c80339 -2134375623 ECS_E_CERT_DATE_INVALID The server's SSL certificate is expired. Check with your organization's tech support to get help. If you need further investigation, create a support request.
0x80c80337 -2134375625 ECS_E_INVALID_CA The server's SSL certificate was issued by a certificate authority that isn't trusted by this PC. Check with your organization's tech support to get help. If you need further investigation, create a support request.
0x80c80001 -2134376447 ECS_E_SYNC_INVALID_PROTOCOL_
FORMAT
A connection with the service could not be established. Please check and configure the proxy setting correctly or remove the proxy setting. Learn more.
0x800706d9 -2147023143 EPT_S_NOT_REGISTERED An external error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80070035 -2147024843 ERROR_BAD_NETPATH An external error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80070571 -2147023503 ERROR_DISK_CORRUPT The disk structure is corrupted and unreadable. Run chkdsk on the volume. Learn more.
0x8007052e -2147023570 ERROR_LOGON_FAILURE Operation failed due to an authentication failure. If the error persists for more than a day, create a support request.
0x8002802b -2147319765 TYPE_E_ELEMENTNOTFOUND An unexpected error occurred. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80072f00 -2147012864 WININET_E_FORCE_RETRY A connection with the service could not be established. No action required. This error should automatically resolve. If the error persists for several days, create a support request.
0x80C86093 -2134351785 ECS_E_STABLEVERSION_SVID_CHECK_
FAILED
The file can't be tiered due to a known issue. No action required. Ignore the error and it will no longer appear once a fix is released.

How to troubleshoot files that fail to be recalled

To troubleshoot files that fail to recall, follow the steps:

  1. In Event Viewer, go to the Microsoft-FileSync-Agent/RecallResults event log.

  2. There is an event logged for each file that is recalled. If the DataTransferHresult field is 0, the file recall is successful. If the DataTransferHresult field has an error code, check the Recall errors and remediation section to see if remediation steps are listed for the error code.

    You can also use PowerShell to view the events that are logged to the RecallResults event log:

    Import-Module "C:\Program Files\Azure\StorageSyncAgent\StorageSync.Management.ServerCmdlets.dll"
    Get-StorageSyncFileRecallResult
    

If content doesn't exist for the error code, follow the general troubleshooting steps:

  1. Verify the file exists in the Azure file share.
  2. Verify the server has Internet connectivity.
  3. Open the Services MMC snap-in and verify the Storage Sync Agent service (FileSyncSvc) is running.
  4. Verify the Azure File Sync filter drivers (StorageSync.sys and StorageSyncGuard.sys) are running:
    • At an elevated command prompt, run fltmc. Verify that the StorageSync.sys and StorageSyncGuard.sys file system filter drivers are listed.

Note

If the server has a lot of recall activities, some errors may be missing from the RecallResults event log due to wrapping. To prevent this issue, go to Event Viewer and increase the RecallResults event log size.

Recall errors and remediation

HRESULT HRESULT (decimal) Error string Issue Remediation
0x80070079 -2147942521 ERROR_SEM_TIMEOUT The file failed to recall due to an I/O timeout. This issue can occur for several reasons: server resource constraints, poor network connectivity, or an Azure storage issue (for example, throttling). No action required. If the error persists for several hours, please open a support case.
0x80070036 -2147024842 ERROR_NETWORK_BUSY The file failed to recall due to a network issue. If the error persists, check network connectivity to the Azure file share.
0x80c80037 -2134376393 ECS_E_SYNC_SHARE_NOT_FOUND The file failed to recall because the server endpoint was deleted. To resolve this issue, see Tiered files aren't accessible on the server after deleting a server endpoint.
0x80070005 -2147024891 ERROR_ACCESS_DENIED The file failed to recall due to an access denied error. This issue can occur if the firewall and virtual network settings on the storage account are enabled and the server does not have access to the storage account. To resolve this issue, add the Server IP address or virtual network by following the steps documented in the Configure firewall and virtual network settings section in the deployment guide.
0x80c86002 -2134351870 ECS_E_AZURE_RESOURCE_NOT_FOUND The file failed to recall because it's not accessible in the Azure file share. To resolve this issue, verify the file exists in the Azure file share. If the file exists in the Azure file share, upgrade to the latest Azure File Sync agent version.
0x80c8305f -2134364065 ECS_E_EXTERNAL_STORAGE_ACCOUNT_
AUTHORIZATION_FAILED
The file failed to recall due to authorization failure to the storage account. To resolve this issue, verify Azure File Sync has access to the storage account.
0x80c86030 -2134351824 ECS_E_AZURE_FILE_SHARE_NOT_FOUND The file failed to recall because the Azure file share isn't accessible. Verify the file share exists and is accessible. If the file share was deleted and recreated, perform the steps documented in the Sync failed because the Azure file share was deleted and recreated section to delete and recreate the sync group.
0x800705aa -2147023446 ERROR_NO_SYSTEM_RESOURCES The file failed to recall due to insufficient system resources.
Note: If the Azure File Sync agent version is 19 or later, and the Storage Sync Agent service (FileSyncSvc) isn't running, you will encounter an error when renaming files or folders within the server endpoint location.
Verify the Storage Sync Agent service (FileSyncSvc) is running. If FileSyncSvc is running and the error persists, investigate which application or kernel-mode driver is exhausting system resources.
0x8007000e -2147024882 ERROR_OUTOFMEMORY The file failed to recall due to insufficient memory. If the error persists, investigate which application or kernel-mode driver is causing the low memory condition.
0x80070070 -2147024784 ERROR_DISK_FULL The file failed to recall due to insufficient disk space. To resolve this issue, free up space on the volume by moving files to a different volume, increase the size of the volume, or force files to tier by using the Invoke-StorageSyncCloudTiering cmdlet.
0x80072f8f -2147012721 WININET_E_DECODING_FAILED The file failed to recall because the server was unable to decode the response from the Azure File Sync service. This error typically occurs if a network proxy is modifying the response from the Azure File Sync service. Please check your proxy configuration.
0x80090352 -2146892974 SEC_E_ISSUING_CA_UNTRUSTED The file failed to recall because your organization is using a TLS terminating proxy or a malicious entity is intercepting the traffic between your server and the Azure File Sync service. If you're certain this is expected (because your organization is using a TLS terminating proxy), follow the steps documented for error CERT_E_UNTRUSTEDROOT to resolve this issue.
0x80c86047 -2134351801 ECS_E_AZURE_SHARE_SNAPSHOT_NOT_
FOUND
The file failed to recall because it's referencing a version of the file which no longer exists in the Azure file share. This issue can occur if the tiered file was restored from a backup of the Windows Server. To resolve this issue, restore the file from a snapshot in the Azure file share.
0x80070032 -2147024846 ERROR_NOT_SUPPORTED An internal error occurred. Please upgrade to the latest Azure File Sync agent version. If the error persists after upgrading the agent, create a support request.
0x80070006 -2147024890 ERROR_INVALID_HANDLE An internal error occurred. If the error persists for more than a day, create a support request.
0x80c80310 -2134375664 ECS_E_INVALID_DOWNLOAD_RESPONSE Azure File sync error. If the error persists for more than a day, create a support request.
0x8007045d -2147023779 ERROR_IO_DEVICE An internal error occurred. If the error persists for more than a day, create a support request.
0x80c8604b -2134351797 ECS_E_AZURE_FILE_SHARE_FILE_NOT_
FOUND
File not found in the file share. You have likely performed an unsupported operation. Learn more. Please find the original copy of the file and overwrite the tiered file in the server endpoint.
0x80070021 -2147024863 ERROR_LOCK_VIOLATION The process cannot access the file because another process has locked a portion of the file. No action required. Once the application closes the handle to the file, recall should succeed.
0x80c8604c -2134351796 ECS_E_AZURE_FILE_SNAPSHOT_NOT_
FOUND_SYNC_PENDING
An internal error occurred. No action required. If the error persists for more than a day, create a support request. Recall should succeed after the sync session completes.
0x80c80312 -2134375662 ECS_E_DOWNLOAD_SESSION_STREAM_
INTERRUPTED
Couldn't finish downloading files. Sync will try again later. If the error persists, use the Test-StorageSyncNetworkConnectivity cmdlet to check network connectivity to the service endpoints. Learn more.
0x80c8600c -2134351860 ECS_E_AZURE_INTERNAL_ERROR The server encountered an internal error. No action required. If the error persists for more than a day, create a support request.
0x80c8600b -2134351861 ECS_E_AZURE_INVALID_RANGE The server encountered an internal error. No action required. If the error persists for more than a day, create a support request.
0x8007045b -2147023781 ERROR_SHUTDOWN_IN_PROGRESS A system shutdown is in progress. No action required. If the error persists for more than a day, create a support request.
0x80072efd -2147012867 WININET_E_CANNOT_CONNECT A connection with the service could not be established. Use the Test-StorageSyncNetworkConnectivity cmdlet to check network connectivity to the service endpoints. Learn more.
0x80072f8f -2147012721 WININET_E_DECODING_FAILED Firewall, proxy or gateway is blocking access to the PKI URLs, or the PKI servers are down. Ensure the server can access the following URLs:

Public cloud endpoints:

https://www.microsoft.com/pki/mscorp/cps
http://crl.microsoft.com/pki/mscorp/crl/
http://mscrl.microsoft.com/pki/mscorp/crl/
http://ocsp.msocsp.com
http://ocsp.digicert.com/
http://crl3.digicert.com/

Azure Government endpoints:

https://www.microsoft.com/pki/mscorp/cps
http://crl.microsoft.com/pki/mscorp/crl/
http://mscrl.microsoft.com/pki/mscorp/crl/
http://ocsp.msocsp.com
http://ocsp.digicert.com/
http://crl3.digicert.com/

Once the Azure File Sync agent is installed, the PKI URL is used to download intermediate certificates required to communicate with the Azure File Sync service and Azure file share. The OCSP URL is used to check the status of a certificate. If the error persists for several days, create a support request.
0x800703ee -2147023890 ERROR_FILE_INVALID The volume for a file has been externally altered so that the opened file is no longer valid. If the error persists for more than a day, create a support request.
0x80c86048 -2134351800 ECS_E_AZURE_FILE_SNAPSHOT_NOT_
FOUND
An internal error occurred. You have likely performed an unsupported operation. Learn more. Please find the original copy of the file and overwrite the tiered file in the server endpoint.
0x80072f78 -2147012744 WININET_E_INVALID_SERVER_RESPONSE A connection with the service could not be established. Use the Test-StorageSyncNetworkConnectivity cmdlet to check network connectivity to the service endpoints. Learn more.
0x8007139f -2147019873 ERROR_INVALID_STATE An internal error occurred. No action required. If the error persists for more than a day, create a support request.
0x80070570 -2147023504 ERROR_FILE_CORRUPT The file or directory is corrupted and unreadable. Run chkdsk on the volume. Learn more.
0x800705ad -2147023443 ERROR_WORKING_SET_QUOTA Insufficient quota to complete the requested service. Monitor memory usage on your server. If the error persists for more than a day, create a support request.
0x80070008 -2147024888 ERROR_NOT_ENOUGH_MEMORY Not enough memory resources are available to process this command. Monitor memory usage on your server. If the error persists for more than a day, create a support request.
0x80c80072 -2134376334 ECS_E_BAD_GATEWAY A connection with the service could not be established. Use the Test-StorageSyncNetworkConnectivity cmdlet to check network connectivity to the service endpoints. Learn more.
0x80190193 -2145844845 HTTP_E_STATUS_FORBIDDEN Forbidden (403) error occurred. Update Azure file share access policy. Learn more.
0x80c8604e -2134351794 ECS_E_AZURE_FILE_SNAPSHOT_NOT_
FOUND_ON_CONFLICT_FILE
Unable to recall sync conflict loser file from Azure file share. If this error is happening for a tiered file that is a sync conflict file, this file might not be needed by end users anymore. If the original file is available and valid, you may remove this file from the server endpoint.
0x80c80075 -2134376331 ECS_E_ACCESS_TOKEN_CATASTROPHIC
_FAILURE
An internal error occurred. No action required. If the error persists for more than a day, create a support request.
0x80c8005b -2134376357 ECS_E_AZURE_FILE_SERVICE_
UNAVAILABLE
The Azure File Service is currently unavailable. If the error persists for more than a day, create a support request.
0x80c83099 -2134364007 ECS_E_PRIVATE_ENDPOINT_ACCESS_
BLOCKED
Private endpoint configuration access blocked. Check the private endpoint configuration and allow access to the Azure File Sync service. Learn more.
0x80c86000 -2134351872 ECS_E_AZURE_AUTHENTICATION_FAILED Server failed to authenticate the request. Check the network configuration and make sure the storage account accepts the server IP address. You can do this by adding the server IP, adding the server's IP subnet, or adding the server vnet to the authorized access control list to access the storage account. Learn more.
0x80072ef1 -2147012879 ERROR_WINHTTP_OPERATION_
CANCELLED
A connection with the service couldn't be established. If the error persists, use the Test-StorageSyncNetworkConnectivity cmdlet to check network connectivity to the service endpoints. Learn more.
0x80c80338 -2134375624 ECS_E_CERT_CN_INVALID The server's SSL certificate contains incorrect hostnames. The certificate can't be used to establish the SSL connection. Check with your organization's tech support to get help. If you need further investigation, create a support request.
0x80c8000c -2134376436 ECS_E_SYNC_UNKNOWN_URI An internal error occurred. No action required. If the error persists for more than a day, create a support request.
0x80c8033a -2134375622 ECS_E_SECURITY_CHANNEL_ERROR There was a problem validating the server's SSL certificate. Check with your organization's tech support to get help. If you need further investigation, create a support request.
0x80131509 -2146233079 COR_E_INVALIDOPERATION An unexpected error occurred. If the error persists for more than a day, create a support request.
0x80c8603d -2134351811 ECS_E_AZURE_UNKNOWN_FAILURE An unexpected error occurred. No action required. If the error persists for more than a day, create a support request.
0x80c8033f -2134375617 ECS_E_TOKEN_LIFETIME_IS_TOO_LONG An internal error occurred. No action required. If the error persists for more than a day, create a support request.
0x80190190 -2145844848 HTTP_E_STATUS_BAD_REQUEST A connection with the service could not be established. No action required. If the error persists for more than a day, create a support request.
0x80c86036 -2134351818 ECS_E_AZURE_FILE_PARENT_NOT_
FOUND
The specified parent path for the file does not exist You have likely performed an unsupported operation. Learn more. Please find the original copy of the file and overwrite the tiered file in the server endpoint.
0x80c86049 -2134351799 ECS_E_AZURE_SHARE_SNAPSHOT_FILE_
NOT_FOUND
File not found in the share snapshot. You have likely performed an unsupported operation. Learn more. Please find the original copy of the file and overwrite the tiered file in the server endpoint.
0x80c80311 -2134375663 ECS_E_DOWNLOAD_SESSION_HASH_
CONFLICT
An internal error occurred. If the error persists for more than a day, create a support request.
0x800700a4 -2147024732 ERROR_MAX_THRDS_REACHED An internal error occurred. No action required. If the error persists for more than a day, create a support request.
0x80070147 -2147024569 ERROR_OFFSET_ALIGNMENT_
VIOLATION
An internal error occurred. If the error persists for more than a day, create a support request.
0x80090321 -2146893023 SEC_E_BUFFER_TOO_SMALL An internal error occurred. If the error persists for more than a day, create a support request.
0x801901a0 -2145844832 HTTP_E_STATUS_RANGE_NOT_
SATISFIABLE
An internal error occurred. If the error persists for more than a day, create a support request.
0x80c80066 -2134376346 ECS_E_CLUSTER_ID_MISMATCH There is a mismatch between the cluster ID returned from cluster API and the cluster ID saved during the registration. Please create a support request for further investigation of the issue.
0x80c8032d -2134375635 ECS_E_PROXY_AUTH_REQUIRED The proxy server used to access the internet needs your current credentials. If your proxy requires authentication, update the proxy credentials. Learn more.
0x8007007a -2147024774 ERROR_INSUFFICIENT_BUFFER An internal error occurred. No action required. If the error persists for more than a day, create a support request.
0x8019012e -2145844946 HTTP_E_STATUS_REDIRECT Azure File Sync does not support HTTP redirection. Disable HTTP redirect on your proxy server or network device.
0x800706be -2147023170 RPC_S_CALL_FAILED An unknown error occurred. If the error persists, use the Test-StorageSyncNetworkConnectivity cmdlet to check network connectivity to the service endpoints. Learn more.
0x80072747 -2147014841 WSAENOBUFS An internal error occurred. If the error persists, use the Test-StorageSyncNetworkConnectivity cmdlet to check network connectivity to the service endpoints. Learn more.
0x80C86093 -2134351785 ECS_E_STABLEVERSION_SVID_CHECK_
FAILED
The file can't be recalled due to a known issue. Copy the file manually from a different endpoint or the cloud share. If you can't copy the file manually, create a support ticket.
0x80C80362 -2134375582 ECS_E_ITEM_PATH_COMPONENT_HAS_
TRAILING_DOT
The file tiering or download failed because of a trailing dot in the path. Rename the trailing dot in the folder or file name.
0x80c83096 -2134364010 ECS_E_MGMT_
STORAGEACLSBYPASSNOTSET
This error occurs if the firewall and virtual network settings are enabled on the storage account and the Allow trusted Microsoft services to access this storage account exception isn't checked. To resolve this issue, follow the steps in Configure firewall and virtual network settings.

Tiered files are not accessible on the server after deleting a server endpoint

Tiered files on a server will become inaccessible if the files aren't recalled prior to deleting a server endpoint or if tiered files were restored from on-premises (third-party) backup to the server endpoint location.

The following errors are logged if tiered files aren't accessible:

  • When syncing a file, error code -2147023890 (0x800703ee - ERROR_FILE_INVALID) or -2147942467 (0x80070043 - ERROR_BAD_NET_NAME) is logged in the ItemResults event log.
  • When recalling a file, error code -2147023890 (0x800703ee - ERROR_FILE_INVALID) or -2134376393 (0x80c80037 - ECS_E_SYNC_SHARE_NOT_FOUND) is logged in the RecallResults event log.

If the tiered files aren't accessible due to deleting the server endpoint, restoring access to your tiered files is possible if the following conditions are met:

  • Server endpoint was deleted within the past 30 days.
  • Cloud endpoint wasn't deleted.
  • File share wasn't deleted.
  • Sync group wasn't deleted.

If the conditions above are met, you can restore access to the files on the server by recreating the server endpoint at the same path on the server within the same sync group within 30 days.

If the conditions above aren't met or the tiered files were restored from an on-premises (third-party) backup, restoring access isn't possible as these tiered files on the server are now orphaned. Follow these instructions to remove the orphaned tiered files.

Note

  • When tiered files aren't accessible on the server, the full file should still be accessible if you access the Azure file share directly.
  • To prevent orphaned tiered files in the future, follow the steps documented in Remove a server endpoint when deleting a server endpoint and don't restore tiered files from on-premises backup, see Disaster recovery best practices with Azure File Sync.

How to get the list of orphaned tiered files

  1. Run the following PowerShell commands to list orphaned tiered files:

    Import-Module "C:\Program Files\Azure\StorageSyncAgent\StorageSync.Management.ServerCmdlets.dll"
    $orphanFiles = Get-StorageSyncOrphanedTieredFiles -path <server endpoint path>
    $orphanFiles.OrphanedTieredFiles > OrphanTieredFiles.txt
    
  2. Save the OrphanTieredFiles.txt output file in case files need to be restored from backup after they're deleted.

How to remove orphaned tiered files

Option 1: Delete the orphaned tiered files

This option deletes the orphaned tiered files on the Windows Server but requires removing the server endpoint if it exists due to re-creation after 30 days or is connected to a different sync group. File conflicts will occur if files are updated on the Windows Server or Azure file share before the server endpoint is recreated.

  1. Back up the Azure file share and server endpoint location.

  2. Remove the server endpoint in the sync group (if it exists) by following the steps documented in Remove a server endpoint.

    Warning

    If the server endpoint isn't removed prior to using the Remove-StorageSyncOrphanedTieredFiles cmdlet, deleting the orphaned tiered file on the server will delete the full file in the Azure file share.

  3. Run the following PowerShell commands to list orphaned tiered files:

    Import-Module "C:\Program Files\Azure\StorageSyncAgent\StorageSync.Management.ServerCmdlets.dll"
    $orphanFiles = Get-StorageSyncOrphanedTieredFiles -path <server endpoint path>
    $orphanFiles.OrphanedTieredFiles > OrphanTieredFiles.txt
    
  4. Save the OrphanTieredFiles.txt output file in case files need to be restored from backup after they're deleted.

  5. Run the following PowerShell commands to delete orphaned tiered files:

    Import-Module "C:\Program Files\Azure\StorageSyncAgent\StorageSync.Management.ServerCmdlets.dll"
    $orphanFilesRemoved = Remove-StorageSyncOrphanedTieredFiles -Path <folder path containing orphaned tiered files> -Verbose
    $orphanFilesRemoved.OrphanedTieredFiles > DeletedOrphanFiles.txt
    

    Note

    • Tiered files modified on the server that aren't synced to the Azure file share will be deleted.
    • Tiered files that are accessible (not orphan) won't be deleted.
    • Non-tiered files will remain on the server.
  6. Optional: Recreate the server endpoint if deleted in step 3.

Option 2: Mount the Azure file share and copy the files locally that are orphaned on the server

This option doesn't require removing the server endpoint but requires sufficient disk space to copy the full files locally.

  1. Mount the Azure file share on the Windows Server that has orphaned tiered files.

  2. Run the following PowerShell commands to list orphaned tiered files:

    Import-Module "C:\Program Files\Azure\StorageSyncAgent\StorageSync.Management.ServerCmdlets.dll"
    $orphanFiles = Get-StorageSyncOrphanedTieredFiles -path <server endpoint path>
    $orphanFiles.OrphanedTieredFiles > OrphanTieredFiles.txt
    
  3. Use the OrphanTieredFiles.txt output file to identify orphaned tiered files on the server.

  4. Overwrite the orphaned tiered files by copying the full file from the Azure file share to the Windows Server.

How to troubleshoot files unexpectedly recalled on a server

Antivirus, backup, and other applications that read large numbers of files cause unintended recalls unless they respect the skip offline attribute and skip reading the content of those files. Skipping offline files for products that support this option helps avoid unintended recalls during operations like antivirus scans or backup jobs.

Consult with your software vendor to learn how to configure their solution to skip reading offline files.

Unintended recalls also might occur in other scenarios, like when you're browsing cloud-tiered files in File Explorer. This is likely to occur on Windows Server 2016 if the folder contains executable files. File Explorer was improved for Windows Server 2019 and later to better handle offline files.

Note

Use Event ID 9059 in the Telemetry event log to determine which application(s) is causing recalls. This event provides application recall distribution for a server endpoint and is logged once an hour.

Process exclusions for Azure File Sync

If you want to configure your antivirus or other applications to skip scanning for files accessed by Azure File Sync, configure the following process exclusions:

  • C:\Program Files\Azure\StorageSyncAgent\AfsAutoUpdater.exe
  • C:\Program Files\Azure\StorageSyncAgent\FileSyncSvc.exe
  • C:\Program Files\Azure\StorageSyncAgent\MAAgent\MonAgentLauncher.exe
  • C:\Program Files\Azure\StorageSyncAgent\MAAgent\MonAgentHost.exe
  • C:\Program Files\Azure\StorageSyncAgent\MAAgent\MonAgentManager.exe
  • C:\Program Files\Azure\StorageSyncAgent\MAAgent\MonAgentCore.exe
  • C:\Program Files\Azure\StorageSyncAgent\MAAgent\Extensions\XSyncMonitoringExtension\AzureStorageSyncMonitor.exe

TLS 1.2 required for Azure File Sync

You can view the TLS settings at your server by looking at the registry settings.

If you're using a proxy, consult your proxy's documentation and ensure it's configured to use TLS 1.2.

See also

Contact us for help

If you have questions or need help, create a support request, or ask Azure community support. You can also submit product feedback to Azure feedback community.