Virus Problem

Has anyone noticed that Symantec AV cleaning tool for the Oprsrv virus leaves and does not detect a file in the Windows \System \Sysbackup called RB000 and recreates it over and over to 001 002 etc. We have searched the registry, deleted the folder,and tried almost everything and it comes back. Note: We disconnect all computers from the network and perform the removals in Safe Mode. We printed out all symantec technical notes and followed them to the letter- still comes back. Any one have a suggestion? All systems are running Windows 98SE with no drive sharing- only specific file sharing- and a firewall is in place.