[Resolved] Backing up System Reserved (SYSVOL) partition failed. Image backup failed

I decided to share the solution to the problem “Backing up System Reserved (SYSVOL) partition failed. Image backup failed”.

Versions:
Server: Ubuntu, 2.5.32
Client: Windows 10, 2.5.25

Log at the server:

Log: (Windows-User25)

Level Time Message
Info 29.05.24 01:04 Starting unscheduled full image backup of volume “C:”…
Errors 29.05.24 01:04 Backing up System Reserved (SYSVOL) partition failed. Image backup failed
Info 29.05.24 01:04 Time taken for backing up client Windows-User25: 1s
Errors 29.05.24 01:04 Backup failed

C:\Program Files\UrBackup\debug.log at client:

2024-05-29 00:51:40: ERROR: backupcom->AddToSnapshotSet(&(Server->ConvertToWchar(selected_vols[i])[0]), GUID_NULL, &additional_refs[i].volid) failed. VSS error code VSS_E_VOLUME_NOT_SUPPORTED
2024-05-29 00:51:40: ERROR: Creating shadowcopy of "D:\" failed.
2024-05-29 00:51:40: ERROR: Creating shadow copy failed. See client log file for details.

Solution:
Under normal operation of Windows, these partitions do not have drive letters. That is, they are not mounted.

In my case, the first partition was mounted as D:, and the second as E:.

After I removed the drive letters D: and E: from these partitions, everything started working. It is necessary to restart the UrBackupClientBackend service on the client.

When creating an image backup of the C drive, UrBackup automatically includes the SYSVOL partition in the backup. Since this partition was mounted as D:, UrBackup attempted to take a snapshot of it. However, the SYSVOL partition is formatted with the FAT32 file system, and Volume Shadow Copy Service (VSS) does not support creating shadow copies for volumes formatted with FAT32. Therefore, creating a snapshot of these partitions fails.

2 Likes

Interesting, and difficult to find. Congratulations!

Were those Disk Management examples created after you had removed the unwanted drive letters from those two partitions? If Disk Management never showed the two partitions with D: and E: then Windows was more confused than normal and I’m even more impressed.

Were those Disk Management examples created after you had removed the unwanted drive letters from those two partitions?

I found the problem and solved it. Then I decided to share this solution on the forum. The drive letters on the screenshots are shown as they were when the problem occurred.