Windows server backup failed with the following :
A volume shadow copy service operation failed. Please check
VSS and SSP application event logs.The writer's timeout expired between freeze and thaw events.
Event viewer said;
The backup operation that started at '2016-02-16T20:35:28.378000000Z' 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 '0x807800A1'. Please review the event details for a solution, and then rerun the backup operation once the issue is resolved.
I tried restarting the Volume Shadow Copy Service and Microsoft Software Shadow Copy Provider but still it failed.