Cutover Migration Sync Error: Transient error ObjectNotFoundException has occurred.

Question

This is a cutover migration to Exchange Online from Exchange Server 2013. No AD sync No ADFS 50 mailboxes total 7 failed with this error: WorkItem : CopyFolder_Calendar Version Store Message : Cannot set search criteria in SearchFolder. Try using fewer keywords at the same time, reducing the number of users in the From, To, Cc, and Bcc fields, and reducing the number of mailboxes that are searched at the same time. --> MapiExceptionInvalidEntryId: Unable to SetSearchCriteria. (hr=0x80040107, ec=-2147221241)

You can get this information running the following ExchangeOnline Powershell command on a failed migration user $r = Get-MigrationUserStatistics bob.smith@contoso.com -IncludeReport $r.Report.Failures[-1]

This will give you the most recent error in the migration user's report.

This was the same type of cutover migration we did for a customer recently that also had this exact issue for a chunk of the mailboxes in the cutover migration.

We have done hundreds of these in the past few years in the exact same way without this issue, so something has changed recently in Exchange Online. Calendar data is not the issue. The calendar folders come over just fine.

I did a lot of troubleshooting on the previous migration that had this issue, and I was able to get it the mailboxes to sync correctly after performing the following actions:

1. Connect to the on-premises Exchange Server 2013 user mailbox via Outlook client.
2. Use MFCMAPI application to hard delete the “Calendar Version Store” folder from the user’s mailbox. NOTE: this did not have any noticeable impact on the user's mailbox or calendar, and we are not concerned with long term effects because we will be decommissioning on-premises Exchange completely after the cutover is finalized.
3. Remove the cloud mailbox and user account that had failed to sync with this error. Restart the cutover migration batch to provision a new cloud mailbox and start the sync again.

After performing these actions, the mailbox syncs without issue and continues to perform incremental syncs without issue as well.

According to Microsoft documentation I found, the Calendar Version Store is a location used to store calendar versioning data for the user’s mailbox. It is in the ROOT of the mailbox and not visible via Outlook. It is an Exchange mailbox default folder. If you do not remove the cloud mailbox that was previously synced with errors, then you will see the following error if you restart the sync for the mailbox. ErrorSummary : Default folders can't be moved or deleted.

This is because the Exchange Online service do not allow removal of this default folder. The sync process will see that it no longer exists in the on-premise mailbox and try to remove it from the cloud mailbox, but it cannot be removed from the cloud mailbox and will give you that error.

Something is wrong with how the target cloud mailbox or migration sync process is handling data for this folder. Again, this is a very recent change that only seems to effect cutover migrations. I have not seen this with mailbox moves in hybrid environments or Exchange Online tenant to tenant mailbox moves. This only occurs with cutover migrations.

It does correspond with the recent removal of the ability to use the Classic Exchange Admin Center to setup a migration endpoint and batch.

Is anyone else having this issue? Has anyone else found a more reasonable fix other than the manual and tedious process that I have been using? Does anyone have any other suggestions or input on this issue?

Answer 1

Hi @ Stephen Biasotto ,

Please try moving the mailbox to another mailbox database, and then perform a cutover migration to see if this error is still reported.

If the above operation is still unsuccessful, we recommend that you could export the failed mailbox data to the PST. Then create a new mailbox in the cloud to import the relevant data.

 

Moreover, I found a similar thread for your reference:

Getting Transient error ObjectNotFoundException has occurred on Outlook anywhere cutover Exchange migration of several mailboxes from Intermedia to Office 365 - Microsoft Q&A

Hope it is helpful to you!

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Answer 2

First, you must double check if the issue is related to only one particular mailbox or all the mailboxes. You can try removing the mailbox with the problem to confirm if the issue persists on other or all the mailboxes in the migration batch.

Check this article for help - https://community.spiceworks.com/how_to/190529-how-to-fix-transient-error-objectnotfoundexception-has-occurred

Please Note: Since the web sites are not hosted by Microsoft, the links may change without notice. Microsoft does not guarantee the accuracy of this information.

Answer 3

Hi Stephen

We are also seeing the same issue on a cutover migration we attempted to run over the weekend from exchange 2013. We are seeing this affect about 75% of mailboxes in a batch of 20. We will try your recommendations to see if they fix the issue.

I haven't been able to identify any obvious differences between the mailboxes that failed and the ones that are ok.

One question it would be useful for MS to answer would be if there is any way to safely and programmatically remove the Calendar Version Store folder from users mailboxes without having to manually connect to each user using the MFCMAPI program?