Configure Microsoft Defender Antivirus exclusions on Windows Server

Applies to:

• Microsoft Defender for Endpoint Plan 1
• Microsoft Defender for Endpoint Plan 2
• Microsoft Defender Antivirus

Platforms

• Windows

Microsoft Defender Antivirus on Windows Server 2016 and Windows Server 2019 automatically enrolls you in certain exclusions, as defined by your specified server role. These exclusions don't appear in the standard exclusion lists that are shown in the Windows Security app.

In addition to server role-defined automatic exclusions, you can add or remove custom exclusions. To do that, refer to these articles:

• Configure and validate exclusions based on file name, extension, and folder location
• Configure and validate exclusions for files opened by processes

A few points to keep in mind

• Custom exclusions take precedence over automatic exclusions.
• Automatic exclusions only apply to real-time protection (RTP) scanning.
• Automatic exclusions aren't honored during a quick scan, full scan, and custom scan.
• Custom and duplicate exclusions don't conflict with automatic exclusions.
• Microsoft Defender Antivirus uses the Deployment Image Servicing and Management (DISM) tools to determine which roles are installed on your computer.
• Appropriate exclusions must be set for software that isn't included with the operating system.
• Windows Server 2012 R2 doesn't have Microsoft Defender Antivirus as an installable feature. When you onboard those servers to Defender for Endpoint, you'll install Microsoft Defender Antivirus, and default exclusions for operating system files are applied. However, exclusions for server roles (as specified below) don't apply automatically, and you should configure these exclusions as appropriate. To learn more, see Onboard Windows servers to the Microsoft Defender for Endpoint service.

This article provides an overview of exclusions for Microsoft Defender Antivirus on Windows Server 2016 or later.

Because Microsoft Defender Antivirus is built into Windows Server 2016 and later, exclusions for operating system files and server roles happen automatically. However, you can define custom exclusions. You can also opt out of automatic exclusions if necessary.

This article includes the following sections:

Section	Description
Automatic exclusions on Windows Server 2016 or later	Describes the two main types of automatic exclusions and includes a detailed list of automatic exclusions
Opting out of automatic exclusions	Includes important considerations and procedures describing how to opt out of automatic exclusions
Defining custom exclusions	Provides links to how-to information for defining custom exclusions

Automatic exclusions on Windows Server 2016 or later

On Windows Server 2016 or later, you shouldn't need to define the following exclusions:

• Operating system files
• Server roles and any files that are added through server roles

Because Microsoft Defender Antivirus is built in, it doesn't require exclusions for operating system files on Windows Server 2016 or later. In addition, when you run Windows Server 2016 or later and install a role, Microsoft Defender Antivirus includes automatic exclusions for the server role and any files that are added while installing the role.

Operating system exclusions and server role exclusions don't appear in the standard exclusion lists that are shown in the Windows Security app.

Note

Automatic exclusions apply only to Windows Server 2016 and later. These exclusions are not visible in the Windows Security app and in PowerShell. Automatic exclusions can apply if your servers running Windows Server 2012 R2 are onboarded to Defender for Endpoint. For more information, see Onboard Windows servers to the Microsoft Defender for Endpoint service. Automatic exclusions for server roles and operating system files do not apply to Windows Server 2012.

The list of automatic exclusions

The following sections contain the exclusions that are delivered with automatic exclusions file paths and file types.

Default exclusions for all roles

This section lists the default exclusions for all roles in Windows Server 2016, Windows Server 2019, and Windows Server 2022.

Important

• Default locations could be different than the locations that are described in this article.
• To set exclusions for software that isn't included as a Windows feature or server role, refer to the software manufacturer's documentation.

Windows "temp.edb" files

• %windir%\SoftwareDistribution\Datastore\*\tmp.edb
• %ProgramData%\Microsoft\Search\Data\Applications\Windows\windows.edb

Windows Update files or Automatic Update files

• %windir%\SoftwareDistribution\Datastore\*\Datastore.edb
• %windir%\SoftwareDistribution\Datastore\*\edb.chk
• %windir%\SoftwareDistribution\Datastore\*\edb\*.log
• %windir%\SoftwareDistribution\Datastore\*\Edb\*.jrs
• %windir%\SoftwareDistribution\Datastore\*\Res\*.log

Windows Security files

• %windir%\Security\database\*.chk
• %windir%\Security\database\*.edb
• %windir%\Security\database\*.jrs
• %windir%\Security\database\*.log
• %windir%\Security\database\*.sdb

Group Policy files

• %allusersprofile%\NTUser.pol
• %SystemRoot%\System32\GroupPolicy\Machine\registry.pol
• %SystemRoot%\System32\GroupPolicy\User\registry.pol

WINS files

• %systemroot%\System32\Wins\*\*.chk
• %systemroot%\System32\Wins\*\*.log
• %systemroot%\System32\Wins\*\*.mdb
• %systemroot%\System32\LogFiles\
• %systemroot%\SysWow64\LogFiles\

File Replication Service (FRS) exclusions

• Files in the File Replication Service (FRS) working folder. The FRS working folder is specified in the registry key HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\NtFrs\Parameters\Working Directory

  • %windir%\Ntfrs\jet\sys\*\edb.chk
  • %windir%\Ntfrs\jet\*\Ntfrs.jdb
  • %windir%\Ntfrs\jet\log\*\*.log

• FRS Database log files. The FRS Database log file folder is specified in the registry key HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Ntfrs\Parameters\DB Log File Directory

  • %windir%\Ntfrs\*\Edb\*.log

• The FRS staging folder. The staging folder is specified in the registry key HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\NtFrs\Parameters\Replica Sets\GUID\Replica Set Stage

  • %systemroot%\Sysvol\*\Ntfrs_cmp*\

• The FRS preinstall folder. This folder is specified by the folder Replica_root\DO_NOT_REMOVE_NtFrs_PreInstall_Directory

  • %systemroot%\SYSVOL\domain\DO_NOT_REMOVE_NtFrs_PreInstall_Directory\*\Ntfrs*\

• The Distributed File System Replication (DFSR) database and working folders. These folders are specified by the registry key HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\DFSR\Parameters\Replication Groups\GUID\Replica Set Configuration File

  Note

  For custom locations, see Opting out of automatic exclusions.

  • %systemdrive%\System Volume Information\DFSR\$db_normal$
  • %systemdrive%\System Volume Information\DFSR\FileIDTable_*
  • %systemdrive%\System Volume Information\DFSR\SimilarityTable_*
  • %systemdrive%\System Volume Information\DFSR\*.XML
  • %systemdrive%\System Volume Information\DFSR\$db_dirty$
  • %systemdrive%\System Volume Information\DFSR\$db_clean$
  • %systemdrive%\System Volume Information\DFSR\$db_lostl$
  • %systemdrive%\System Volume Information\DFSR\Dfsr.db
  • %systemdrive%\System Volume Information\DFSR\*.frx
  • %systemdrive%\System Volume Information\DFSR\*.log
  • %systemdrive%\System Volume Information\DFSR\Fsr*.jrs
  • %systemdrive%\System Volume Information\DFSR\Tmp.edb

Process exclusions

• %systemroot%\System32\dfsr.exe
• %systemroot%\System32\dfsrs.exe

Hyper-V exclusions

The following table lists the file type exclusions, folder exclusions, and process exclusions that are delivered automatically when you install the Hyper-V role.

Exclusion type	Specifics
File types	*.vhd *.vhdx *.avhd *.avhdx *.vsv *.iso *.rct *.vmcx *.vmrs
Folders	%ProgramData%\Microsoft\Windows\Hyper-V %ProgramFiles%\Hyper-V %SystemDrive%\ProgramData\Microsoft\Windows\Hyper-V\Snapshots %Public%\Documents\Hyper-V\Virtual Hard Disks
Processes	%systemroot%\System32\Vmms.exe %systemroot%\System32\Vmwp.exe

SYSVOL files

• %systemroot%\Sysvol\Domain\*.adm
• %systemroot%\Sysvol\Domain\*.admx
• %systemroot%\Sysvol\Domain\*.adml
• %systemroot%\Sysvol\Domain\Registry.pol
• %systemroot%\Sysvol\Domain\*.aas
• %systemroot%\Sysvol\Domain\*.inf
• %systemroot%\Sysvol\Domain\*Scripts.ini
• %systemroot%\Sysvol\Domain\*.ins
• %systemroot%\Sysvol\Domain\Oscfilter.ini

Active Directory exclusions

This section lists the exclusions that are delivered automatically when you install Active Directory Domain Services (AD DS).

NTDS database files

The database files are specified in the registry key HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\NTDS\Parameters\DSA Database File

• %windir%\Ntds\ntds.dit
• %windir%\Ntds\ntds.pat

The AD DS transaction log files

The transaction log files are specified in the registry key HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\NTDS\Parameters\Database Log Files Path

• %windir%\Ntds\EDB*.log
• %windir%\Ntds\Res*.log
• %windir%\Ntds\Edb*.jrs
• %windir%\Ntds\Ntds*.pat
• %windir%\Ntds\TEMP.edb

The NTDS working folder

This folder is specified in the registry key HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\NTDS\Parameters\DSA Working Directory

• %windir%\Ntds\Temp.edb
• %windir%\Ntds\Edb.chk

Process exclusions for AD DS and AD DS-related support files

• %systemroot%\System32\ntfrs.exe
• %systemroot%\System32\lsass.exe

DHCP Server exclusions

This section lists the exclusions that are delivered automatically when you install the DHCP Server role. The DHCP Server file locations are specified by the DatabasePath, DhcpLogFilePath, and BackupDatabasePath parameters in the registry key HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\DHCPServer\Parameters

• %systemroot%\System32\DHCP\*\*.mdb
• %systemroot%\System32\DHCP\*\*.pat
• %systemroot%\System32\DHCP\*\*.log
• %systemroot%\System32\DHCP\*\*.chk
• %systemroot%\System32\DHCP\*\*.edb

DNS Server exclusions

This section lists the file and folder exclusions and the process exclusions that are delivered automatically when you install the DNS Server role.

File and folder exclusions for the DNS Server role

• %systemroot%\System32\Dns\*\*.log
• %systemroot%\System32\Dns\*\*.dns
• %systemroot%\System32\Dns\*\*.scc
• %systemroot%\System32\Dns\*\BOOT

Process exclusions for the DNS Server role

• %systemroot%\System32\dns.exe

File and Storage Services exclusions

This section lists the file and folder exclusions that are delivered automatically when you install the File and Storage Services role. The exclusions listed below don't include exclusions for the Clustering role.

• %SystemDrive%\ClusterStorage
• %clusterserviceaccount%\Local Settings\Temp
• %SystemDrive%\mscs

Print Server exclusions

This section lists the file type exclusions, folder exclusions, and the process exclusions that are delivered automatically when you install the Print Server role.

File type exclusions

• *.shd
• *.spl

Folder exclusions

This folder is specified in the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Print\Printers\DefaultSpoolDirectory

• %system32%\spool\printers\*

Process exclusions

• spoolsv.exe

Web Server exclusions

This section lists the folder exclusions and the process exclusions that are delivered automatically when you install the Web Server role.

Folder exclusions

• %SystemRoot%\IIS Temporary Compressed Files
• %SystemDrive%\inetpub\temp\IIS Temporary Compressed Files
• %SystemDrive%\inetpub\temp\ASP Compiled Templates
• %systemDrive%\inetpub\logs
• %systemDrive%\inetpub\wwwroot

Process exclusions

• %SystemRoot%\system32\inetsrv\w3wp.exe
• %SystemRoot%\SysWOW64\inetsrv\w3wp.exe
• %SystemDrive%\PHP5433\php-cgi.exe

Turning off scanning of files in the Sysvol\Sysvol folder or the SYSVOL_DFSR\Sysvol folder

The current location of the Sysvol\Sysvol or SYSVOL_DFSR\Sysvol folder and all the subfolders is the file system reparse target of the replica set root. The Sysvol\Sysvol and SYSVOL_DFSR\Sysvol folders use the following locations by default:

• %systemroot%\Sysvol\Domain
• %systemroot%\Sysvol_DFSR\Domain

The path to the currently active SYSVOL is referenced by the NETLOGON share and can be determined by the SysVol value name in the following subkey: HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Netlogon\Parameters

Exclude the following files from this folder and all its subfolders:

• *.adm
• *.admx
• *.adml
• Registry.pol
• Registry.tmp
• *.aas
• *.inf
• Scripts.ini
• *.ins
• Oscfilter.ini

Windows Server Update Services exclusions

This section lists the folder exclusions that are delivered automatically when you install the Windows Server Update Services (WSUS) role. The WSUS folder is specified in the registry key HKEY_LOCAL_MACHINE\Software\Microsoft\Update Services\Server\Setup

• %systemroot%\WSUS\WSUSContent
• %systemroot%\WSUS\UpdateServicesDBFiles
• %systemroot%\SoftwareDistribution\Datastore
• %systemroot%\SoftwareDistribution\Download

Opting out of automatic exclusions

In Windows Server 2016 and later, the predefined exclusions delivered by Security intelligence updates only exclude the default paths for a role or feature. If you installed a role or feature in a custom path, or you want to manually control the set of exclusions, make sure to opt out of the automatic exclusions delivered in Security intelligence updates. But keep in mind that the exclusions that are delivered automatically are optimized for Windows Server 2016 and later. See Recommendations for defining exclusions before defining your exclusion lists.

Warning

Opting out of automatic exclusions may adversely impact performance, or result in data corruption. The exclusions that are delivered automatically are optimized for Windows Server 2016, Windows Server 2019, and Windows Server 2022 roles.

Because predefined exclusions only exclude default paths, if you move NTDS and SYSVOL folders to another drive or path that is different from the original path, you must add exclusions manually. See Configure the list of exclusions based on folder name or file extension.

You can disable the automatic exclusion lists with Group Policy, PowerShell cmdlets, and WMI.

Use Group Policy to disable the auto-exclusions list on Windows Server 2016, Windows Server 2019, and Windows Server 2022

1. On your Group Policy management computer, open the Group Policy Management Console. Right-click the Group Policy Object you want to configure, and then select Edit.

2. In the Group Policy Management Editor go to Computer configuration, and then select Administrative templates.

3. Expand the tree to Windows components > Microsoft Defender Antivirus > Exclusions.

4. Double-click Turn off Auto Exclusions, and set the option to Enabled. Then select OK.

Use PowerShell cmdlets to disable the auto-exclusions list on Windows Server

Use the following cmdlets:

Set-MpPreference -DisableAutoExclusions $true

To learn more, see the following resources:

• Use PowerShell cmdlets to configure and run Microsoft Defender Antivirus.
• Use PowerShell with Microsoft Defender Antivirus.

Use Windows Management Instruction (WMI) to disable the auto-exclusions list on Windows Server

Use the Set method of the MSFT_MpPreference class for the following properties:

DisableAutoExclusions

For more information and allowed parameters, see:

• Windows Defender WMIv2 APIs

Defining custom exclusions

If necessary, you can add or remove custom exclusions. To do that, see the following articles:

• Configure and validate exclusions based on file name, extension, and folder location
• Configure and validate exclusions for files opened by processes

Tip

If you're looking for Antivirus related information for other platforms, see:

• Set preferences for Microsoft Defender for Endpoint on macOS
• Microsoft Defender for Endpoint on Mac
• macOS Antivirus policy settings for Microsoft Defender Antivirus for Intune
• Set preferences for Microsoft Defender for Endpoint on Linux
• Microsoft Defender for Endpoint on Linux
• Configure Defender for Endpoint on Android features
• Configure Microsoft Defender for Endpoint on iOS features

See also

• Exclusions for Microsoft Defender for Endpoint and Microsoft Defender Antivirus
• Configure and validate exclusions for Microsoft Defender Antivirus scans
• Configure and validate exclusions based on file name, extension, and folder location
• Configure and validate exclusions for files opened by processes
• Common mistakes to avoid when defining exclusions
• Customize, initiate, and review the results of Microsoft Defender Antivirus scans and remediation
• Microsoft Defender Antivirus in Windows 10