Backups fail with the following error:
"Unable to execute request (111). Unable to create snapshot using Volume Shadow Copy Service. VSS: 0x80042316. -2147221504"
Please see the following KB article to confirm that the VSS Writers are functioning properly:
The error code 0x80042316 is coming from the Volume Shadow Copy service. This error indicates that VSS is currently running and that another instance cannot be started. This could be due to another application leveraging VSS prior to the RMAD backup running or a snapshot process is still running from a previous call to VSS.
Change the backup time for the DCs that are failing with the error to a different time when there are no other applications scheduled to use VSS. If the error still occurs, restart the VSS service prior to running the backup.