My computer has multiple M2 drive support. In addition to other SSD's, there are 2 x 1TB NVME drives.

These drives have Windows 11 and Windows 10 partitions. The second drive is a clone of the first drive. (Not RAID, they are stand-alone with periodic volume copies using Paragon Hard Disk Manager.)

Currently, I'm in the process of transferring the programs and functions from the Windows 10 OS image to the Windows 11 image. This means that I occasionally need to boot the Windows 10 to access the programs that haven't been migrated to Windows 11 yet.

I have a backup job that is scheduled to run at logon to backup my user profile documents.

Recently, I noticed that it was failing. The backup job hangs at the VSS processing step: "Initializing VSS technology, please wait ..." Checking the Windows System Event log, it reports that the Volume Shadow Service has stopped unexpectedly.

The Windows 10 OS can create Shadow Copies manually. The file system has been checked using Windows and Paragon file systems tools.

Checking the diagnostic logs capture by the Paragon Logs Collector Tool, the "C_\Windows\Logs\Paragon Software\VssRequester\<YYYY-MM-DD.log>" only contains the beginning entry:
2023-03-18 08:09:49.825,I, 13352,VssRequester, Enter CreateVSSSnapshot(). m_BackupType = 1; r_includedVolumes = "\\?\Volume{17213ef6-a138-46be-66f7-2f82fea6c300}\ "; r_includedWriters: r_excludedWriters:

There is no "Snapshot has been successfuly created." entry.

Interesting, because the second drive has a fairly recent, (1 month old), clone of the Windows 10 image, I booted that image to see if a recent Windows update might be causing this behavior?

I ran the same backup job and it succeeded. I updated the Windows patches and reran the backup. It also succeeded.

At this point I decided it by be simpler to copy the working OS image from the second drive back to the first drive to solve the problem. After doing that, I ran the backup job. It failed in the same way!

Again, Windows VSS Snapshots work. Paragon Backups via Hard Drive Manager don't.

Has anyone else experiences this?

Is there a way to generate more verbose logging the backup process, particularly the VSS process?

I have submitted a support ticket with Technical Support, but don't expect a response for some time.