If the VSS writers employed during a backup or replication snapshot process do not finish the shadow copy creation or deletion tasks before/after a snapshot is taken, corrupt shadow copies may be left behind on the source machine(s). These corrupt shadow copies cannot be deleted by issuing the "vssadmin delete shadows /all" command. Instead, you receive the error:


"Error: Snapshots were found, but they were outside of your allowed context. Try removing them with the backup application which created them."


Solution

Launch an elevated command prompt on the Agent machine(s) involved and type the following:


diskshadow <enter>

list shadows all <enter>

delete shadows set  {id of shadow to be deleted if selective deletion is to be performed}<enter>


OR


delete shadows all {if all shadows are to be deleted}.


This will delete the corrupted shadow copies.