Missing GroupWise User

Is it possible to have one GroupWIse user to “disappear” from the postoffice. This person has “disappeared” from the global mail list. The mail folders, etc. are gone. Addressses are gone. The user still exists in NetWare 5.1 – the user just “disappeared” from GroupWise. No other GW users were affected. Could it have been a system glitch? Could this have been accomplished without the someone with Administrative privileges purposely deleting them? Is there a log anywhere which would show if someone had purposely deleted them?