SYMPTOMS
1. Backup jobs are failing with "Error creating volume snapshot(s): VSS_E_VOLUME_NOT_SUPPORTED"
2. Backups jobs are created using policy.
3. Only one or few of backup jobs of the same policy failed. There are no VSS errors in System Event Logs.
4. Expanding the Backup Selection Set "Fixed Drives" of the particular policy reveals a different set of drives from the backup client that is failing. Example: Backup Selection (C:\ D:\) Client (C:\ E:\). However the policy is supposed to backup all "Fixed Drives"
During creation of Backup Selection Set, the Backup Selection Set "Fixed Drives" is not created correctly. As per the above example, C:\ and D:\ are selected individually instead of just selecting "Fixed Drives" without expanding it. Thus when backup is triggered, the backup client is looking for D:\ drive which does not exist in the client and will fail with this error.
