I have a Windows Server 2012 R2 with TFS 2015 Update 2 installed. I configured Scheduled backups in TFS Administration Console.
When I manually take a full backup, everything works and the backupfiles are nicely dropped on a networkshare.
However, the automatic backup (at night) fails.
From the event viewer: Exception Message: Cannot open backup device '\\...\Tfs_Configuration_9859327876866326120F.bak'. Operating system error 0x80090006(Invalid Signature.). BACKUP DATABASE is terminating abnormally. (type SqlException)
Help is much appreciated!
Mapping the network drive solved the problem!