More information

Windows Defender antivirus

Restart requirement

This update does not require a restart. The installer stops the required services, applies the update, and then restarts the services. However, if the required services cannot be stopped for any reason, or if required files are being used, this update will require a restart. If this behavior occurs, you receive a message that advises you to restart. For more information about why you may be prompted to restart your computer, see the following Knowledge Base article:

887012 Why you may be prompted to restart your computer after you install a security update on a Windows-based computer  

Removal information

This update can be uninstalled.  

Verification of the update installation

To verify that the update was applied to an affected system, follow these steps:

  1. Open the Windows Security program. For example, type Security in the Search bar, and select the Windows Security program.

  2. In the navigation pane, select Virus & threat protection.

  3. Under Virus & threat protection updates in the main window, select Check for updates

  4. Select Check for updates again.

  5. In the navigation pane, select Settings, and then select About.

  6. Examine the Engine Version number. The update was successfully installed if the Malware Protection Engine version number or the signature package version number matches or exceeds the version number that you are trying to verify as installed. 

Microsoft Antimalware for Azure

Restart requirement

This update does not require a restart. The installer stops the required services, applies the update, and then restarts the services. However, if the required services cannot be stopped for any reason, or if required files are being used, this update will require a restart. If this behavior occurs, you receive a message that advises you to restart. For more information about why you may be prompted to restart your computer, see the following Knowledge Base article:

887012 Why you may be prompted to restart your computer after you install a security update on a Windows-based computer  

Removal information

This update cannot be uninstalled.  

Verification of the update installation

To verify that the update was applied to an affected system, follow these steps:

  1. Open the malware protection program that you are using.

  2. Select Help, and then select About Microsoft Endpoint Protection

  3. Examine the Engine Version number. The update was successfully installed if the Malware Protection Engine version number or the signature package version number matches or exceeds the version number that you are trying to verify as installed.

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