We recently installed Azure AD Connect on one of our VMs that has been backing up fine for a year. Once Azure AD Connect was put on though, the backups for this VM started failing with the same error as above:
Unable to release guest. Error: Unfreeze error: [Backup job failed.
Cannot create a shadow copy of the volumes containing writer's data.
Has there been any progress with this? I called support and they are sending me a generic article on troubleshooting the error, but since this seems to be related to MS Azure products, I wanted to check here too.