Is this normal?

PS C:\Users\Homer> vssadmin list ShadowStorage
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.

Error: The shadow copy provider had an unexpected error while trying to process
the specified command.

Event viewer says:

Volume Shadow Copy Service error: Error calling a routine on a Shadow Copy Provider {b5946137-7b9f-4925-af80-51abd60b20d5}. Routine details IVssSnapshotProvider::QueryVolumesSupportedForSnapshots(ProviderId,-1,...) [hr = 0x8000ffff, Catastrophic failure

COM+ Event System and VSS are both running.

PS C:\Users\Homer> vssadmin list providers
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.

Provider name: 'Microsoft Software Shadow Copy provider 1.0'
   Provider type: System
   Provider Id: {b5946137-7b9f-4925-af80-51abd60b20d5}
   Version: 1.0.0.7

UrBackup works fine, I can still create Windows restore points (although I’m not sure I need to any more, now that I have UrBackup images), and there are no other issues with this system, so this isn’t really a bug report as such. I’m just curious about what’s causing this error.

Is this expected behaviour for a non-server version of Windows (Win7 Ultimate), for example, or is this something to do with the UrBackup CBT?

No, it’s not normal, but I am relatively certain it is not caused by UrBackup or the CBT driver. Does this persist after reboot?

Yes.

Further research suggests that this problem can be caused by having certain “image mounters” on the system, and actually I have not just one but many, including Daemon Tools, Virtual CD, ImDisk, MagicISO, and probably a few more I’ve forgotten about. I also have AnyDVD, which maps real optical media hardware through a driver to a virtual device that removes any offending DRM. Daemon Tools also includes its own SPTD driver. Acronis True Image also mounts its own disk images.

Any one of those might be responsible, but I’m not going to uninstall them to find out. I’ll just live without the ability to monitor snapshot utilisation.

Anyway, I’m fairly certain it has nothing to do with UrBackup.

Solved it.

It turns out that VSS really doesn’t like VeraCrypt mounted devices, unless they’re mounted as removable media.

PS C:\Users\Homer> vssadmin list ShadowStorage
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.

Shadow Copy Storage association
   For volume: (C:)\\?\Volume{51b6f091-42df-11e5-926c-806e6f6e6963}\
   Shadow Copy Storage volume: (C:)\\?\Volume{51b6f091-42df-11e5-926c-806e6f6e6963}\
   Used Shadow Copy Storage space: 611.906 MB (0%)
   Allocated Shadow Copy Storage space: 1.063 GB (0%)
   Maximum Shadow Copy Storage space: 10 GB (1%)