A few days ago I updated a Veeam Backup & Replication running on a domain controller (really small environment) from v8 to v9, as soon as the the backup ran the next time I received a warning saying that the “ SQL VSS Writer is missing: databases will be backed up in crash-consistent state“. As from now this warning came with every backup.
I searched a bit around and came across the KB 2095
It says: In the case of SBS machines that are also Domain Controllers, ensure that the SQL Writer is running as a domain administrator and not local system
I was not running an environment with a Small Business Server, but who cares? 😉 I checked the SQL Writer Service and changed the user running it to the domain administrator and now the backup works without a warning 😎
I guess this applies to all systems that run Active Directory Domain Controller along with SQL (typical in SBS servers). I had the same issue, solved it the same way.