Event 521, Backup

If you are using the builtin Windows Server Backup and receive the following error message, especially on servers running Hyper-V:

The backup operation that started at ‘‎2011‎-‎09‎-‎19T19:00:58.551000000Z’ has failed because the Volume Shadow Copy Service operation to create a shadow copy of the volumes being backed up failed with following error code ‘2155348001’. Please review the event details for a solution, and then rerun the backup operation once the issue is resolved.

This might be caused by a timeout while creating the Shared Protection Point (SPP). The default timeout is 10 minutes and can be increased by setting/creating a registry value.

Under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SPP you will find a DWORD value called CreateTimeout that is set to a decimal value of 6000000 which is 10 minutes. Set it to for example 12000000 and rerun your backup.

If the value does not exist you will have to create it.