I have a PC running WinXP SP2 with the Novell Client 4.91 SP2 that has
been running for about 6 months with no problems. Then on Dec. 23rd
(with no known system changes) it began failing on every login.

If you attempt to login to the Tree, you receive the following
error: 'SAS Window: winlogon.exe - Application Error > The instruction
at "0x58f0c236" referenced memory at "0x00000014". The memory could not
be "read"'. It then will give you the chance to "Cancel" or "Debug".
Either will promptly blue-screen the computer.

If you attempt to login "WorkStation Only". You are able to get into
windows, but it will imediately give a fatal exception error in
winlogon.exe. If you send this report to Microsoft, it responds with a
winlogon trojan/virus message. The event log will also show several
messages indicating that the faulting module is lgnwnt32.dll.

If you remove the Novell Client all together, everything works fine.

I have done the following in attempt to correct the issue:

- Scanned the PC for viruses (With three different programs) - Nothing

- Scanned the PC for Spyware/Malware (With two different programs) -
Nothing found.

- Scanned the PC with HijackThis - Nothing unknown or suspicious.

- Removed the original Novell Client and reinstalled version 4.91 SP3
severl times in different configuration. Including Typical, Custom(No
NMAS/No NICI/IPX Only) and Custom(No NMAS/IP and IPX)

- Ensured that all Windows Updates are applied

Any help would be greatly appreciated.