Outlook crashes and has to restart with no explanation.

Trying to move email from home folder to shared folder. Also trying to delete items or emails from a shared folder. Same issue with a calendar.

Running SBE Outlook 2003 version 11.8217.8221 SP3
Windows XP Pro SP3

Zimbra Client v 5.0.2706.9
Server v 5.09_GA_2500