Error: Azure Backup fails Everyday and cannot decipher error message:

Hello Graham,

Going through the error message associated with the code 100075, seems like the backup failed because the snapshot operation for one or more volumes selected for backup could not be initiated.

Can you please ensure that the volume is not on a VHD that is contained in another VHD? Also, ensure that any files located on a VHD are not protected simultaneously along with files on the volume containing the VHD.

If a volume on a VHD that is contained in another VHD, that volume becomes nested too deeply to participate in the VSS operation. Possible reasons for this error include the following:

Trying to create a shadow copy of a volume that resides on a VHD that is contained in another VHD.

Trying to create a shadow copy of a VHD volume when the volume that contains the VHD is also in the same shadow copy set.

Let us know if you are still facing any issues.

Thanks,

Maanas Saran