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Issue: Running the SBS backup on SBS 2011 fails with the warning below even though backup drive and system drives have enough free space:
There is not enough disk space to create the volume shadow copy on the storage location. Make sure that, for all volumes to be backup up, the minimum required disk space for shadow copy creation is available. For the optimal experience, we recommend at least 1 gigabyte of free disk space on each volume being backed up.
Event viewer shows this error:
Log Name: Application Source: Microsoft-Windows-Backup Date: 16/10/2013 20:00:35 Event ID: 521 Task Category: None Level: Error Keywords: User: SYSTEM Description:The backup operation that started at ‘2013-10-16T19:00:19.141000000Z’ 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 ‘‘. Please review the event details for a solution, and then rerun the backup operation once the issue is resolved.
Resolution: Run fsutil command to delete and disable journal
Taken from