Forum Discussion
ReFS volume inaccessible after update from Windows 10 22H2 to Windows 11 23H2
Since opening this thread in December, I'd like to share two "solutions" (workarounds):
1) As mentioned before, I attached the ReFS 3.4 volume which wouldn't read on Windows 11, to a Windows Server 2022 system, which auto-updated it to ReFS 3.7. Moving the disks back to the Windows 11 system, I can confirm that they now work fine. Storage Spaces on Windows 11 prompted to upgrade the pool, but the data was readable both before and after this upgrade. The ReFS version remained unchanged at 3.7. This solution does not require purchasing new disks, but it does require access to a Windows Server 2022 system.
2) The other method is to get new disks and copy the data, using an OS version like Windows 10, which can read the ReFS 3.4 volume which became unreadable after the upgrade to Windows 11.
Thanks for this post. I hit this issue after doing an in-place upgrade of Windows 10 23H2 Enterprise to Windows 11 24H2 Enterprise. A secondary disk (not the OS disk) was formatted as ReFS. In fact, all attempts to upgrade to 11 23H2 failed; even booting from the ISO caused a blue screen--I wonder if the ReFS volume was the issue. At least the 24H2 upgrade worked, but then I had an unreadable volume.
To get access to the data, I booted from a Windows 10 installer ISO, got to a command prompt, and used RoboCopy to copy data from the ReFS disk to an NTFS disk. First use diskpart with "list vol" to get the drive letters as assigned in the recovery environment. Then, for example, to copy a E:\VMExport folder to F:\DriveE\VMExport:
robocopy "E:\VMExport" "F:\DriveE\VMExport" /E /B /XJ /DCOPY:T /COPY:DAT /R:0 /W:0
The params are described here;
https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/robocopy