calendar won't sync

I can sync other items (contacts, notes, favourites, etc) when calendar is
not listed. When the calendar is listed the sync fails. When only the
calendar is listed the sync still fails. I get the message: "ActiveSync has
encountered a problem and needs to close." Having the calendar is my most
important need. I hope somebody can help.
Stats: XP Prof 5.1; ActiveSync 4.2; 2000 Exchange Server; Outlook 2002 SP3;
UTStarcom 6700 with 1 gig extra memory
Additional Info: Outlook is primary e-mail client; Outlook is online; Pocket
PC is running; ran troubleshooter: "no issues"