ReFS volume appears RAW (version doesn't match expected value) after Windows Update

New Contributor

After Windows Update last night, Windows Server 2019 wouldn't mount a storage space volume as ReFS (it appears as RAW). The error in the ReFS event log is "ReFS failed to mount the volume. Version 1.2 doesn't match expected value 3.4" No issues that I can see at the storage space level (it is a mirrored disk). The volume was working fine before Windows Update and the reboot. Another ReFS volume still works fine after the update.


Any clues? I could not find this error mentioned anywhere else. Thanks.

6 Replies
best response confirmed by MikeMoos (New Contributor)
I solved this by uninstalling KB5009557. The ReFS volume came back working as it should, instead of appearing as RAW.
I will tag along in the hope if @microsoft will acknowledge or come with a mitigation for it.
It seems to be a known issue for the 2022-01 patches.
We ran into this on a Server 2012 server and had to uninstall both KB5009595 and KB5009624 before our drives came back.


Same problem here on Windows 2012R2. We have to uninstall both, KB5009595 and KB5009624. After uninstallation our ReFS File Sytem came back!

Microsoft just released a series of out-of-band updates (KB5010790 for Windows Server 2016, KB5010793 for Windows 10, KB5010795 for Windows 11, KB5010796 for Windows Server 2022, KB5010794 for older systems, etc.) to address the ReFS issue. For some reason they still claim the bug to be limited to removable media, even if that was not the case for me and others.


Alas, I could not find an out-of-band update for Windows Server 2019. So far, no KB page and no Windows Update showing up. ReFS is still broken by re-applying the current (January 18) KB5009557.