Microsoft: Windows 11 22H2 causes file copy performance hit

Microsoft has confirmed a new known issue causing customers to experience a significant performance hit when copying large files over SMB after installing the Windows 11 22H2 update.

While Redmond hasn’t shared how much longer such file operations will take on affected systems, user reports say that the amount of time needed could more than double in some conditions.

Microsoft has shared additional information regarding this issue in a support document detailing the contents of the KB5017389 preview cumulative update released a week ago.

“Copying large multiple gigabyte (GB) files might take longer than expected to finish on Windows 11, version 22H2,” Microsoft revealed.

“You are more likely to experience this issue copying files to Windows 11, version 22H2 from a network share via Server Message Block (SMB) but local file copy might also be affected.”

The company added that Windows devices used in home networks or small offices are less likely to be affected by this newly acknowledged issue.

Workaround available

Microsoft also shared a workaround for customers affected by this known issue after updating their devices to Windows 11 22H2.

As Redmond explains, impacted users can mitigate the file copying performance hit over SMB with the help of file copy tools that don’t use cache manager (buffered I/O).

You can do this using the built-in robocopy and xcopy tools and the commands listed below:

robocopy \\someserver\someshare c:\somefolder somefile.img /J

OR

xcopy \\someserver\someshare c:\somefolder /J

Microsoft is currently investigating this issue and working on a fix that could address it. An update will be provided with an upcoming release.

Since Windows 11 22H2 was released, Microsoft has added compatibility holds to block the upgrade from being offered on some systems due to printer issues or blue screens.

The company also confirmed this week that the Windows 11 2022 Update is also breaking provisioning, leaving Windows 11 endpoints partially configured and failing to finish installing.

Windows 11 22H2 entered a new deployment phase on Tuesday, October 4, and it is now available to all seekers on eligible devices.

Original Posts: Microsoft: Windows 11 22H2 causes file copy performance hit