Outlook 2003 Application Error on Exiting

Eight weeks ago, I began to experience two different types of errors when exiting Outlook 2003 on one specific client. Both seem to have started at the same time. I get one or the other on exiting - but not both. It happens 100% of the time.

1. Even though it is already closing - the "Outlook has experienced a problem and has to close - do you want to report this problem to Microsoft?" dialogue box appears.

or

2. "The instruction at "0x0749a22d" referenced memory at "0x07533550 ". The memory could not be "read ". Click on OK to terminate the program." The message is always the same, but the instruction and referenced memory location numbers change from occasion to occasion.

I have run detect and repair. I have run repair installation from the original Office disk. I have repaired the .ost file, None have fixed the problem.

It is machine specific - If I log into the email account from another computer on the network - the problem does not appear.

I'm running Outlook 2003 [with Office 2003] on a networked Windows XP Professional SP3 client. The network server is Windows Server 2003 SP2.

Anti Virus is McAfee Virus Scan Enterprise 8.7.0.i

Any thoughts on resolving?