Exchange 2003 server keeps falling over

[elb]

[LRS-EXCH-SRVR]: AAVM - scanning error: CallGuiVirusProc: unhandled exception!, 7C82F527.

The 2 main 'faults' appear to be
1) Mail stops being sorted, and sits in pending queue. This always corresponds to an error message from avast.
2) Avast service stops working, cant be restarted, server is rebooted.

I know this is too short for anyone to say 'aha, you need to do a,b,c'. But if anyone can give me a 'lookup XYZ' or 'go read this'  It would be a great help.

Thanks

[Vlk]

Please check the folder <avast>\data\log. Does it contain any files called unpXXXX (where XXXX is a number)? If so, please send them to my email address...


Thanks
Vlk

[elb]

Ta Vlk, have emailed them through