A number of working copies appear when viewing Group Policy objects in the Microsoft Group Policy Management Console (GPMC).
An error may have occurred during a deploy or check in, as a result GPO Admin could not clean up the working copy.
The first thing to do is to verify that all of the working copies are indeed orphaned by counting the number of working copies seen in GPMC to and comparing that number to the number of checked out GPOs using the Checked out search folder logged in to GPOADmin as an Administrator.
A working copy can be orphaned for a few reasons. If an error occurred during the check-in process, then it is possible that the working copy could be orphaned. This is most likely the cause.
Service Account Permissions, check that the service account has the required permissions to delete the working copy. You would only need to check this if the service account is a minimum permissions account. It might be possible that the user did not select "This object and all child objects/This object and all descendant objects" when configuring the permissions for the service account.
Workaround:
*Note
GPOADmin 5.10 and later provides a PowerShell cmdlet that will list all orphaned working copies, Get-OrphanedWorkingCopies. The syntax is:
