If your version of Symantec Event Handler driver (Symevent.sys) is outdated, or if there is a Computer Associates (CA) INO_FLTR.SYS OpLock interoperability problem with the Srv.sys file, you will experience various problems when you work with files over the network on your server?
The following file versions are known to cause problems:
Symevent.sys Symantec Corporation 11.4:0.6 05-Mar-2004 Symantec Event Library Symtdi.sys Symantec Corporation 5.3:6.13 23-Dec-2004 Network Dispatch Driver Ino_flpy.sys Computer Associates 5.0:6100.106 19-Jun-2003 CA eTrust Antivirus/InoculateIT File System Mounting Filter Driver Ino_fltr.sys Computer Associates 5.0:6100.136 08-Aug-2004 CA eTrust Antivirus/InoculateIT File System Filter DriverSee 10484 » Hardware and Software Third-Party Vendor Contact List.
For additional information, see Microsoft Knowledge Base article 923360:
You may experience various problems when you work with files over the network on a Windows Server 2003-based or Windows 2000 Server-based computer