Meeting Request with Cached Exchange Mode

With Cached Exchange Mode turned on, when creating a meeting request if I
click on the "Scheduling" tab, I get the message "The operation could not be
completed because an offline address book is not available. Download an copy
of the offline address book." I followed the directions for downloading an
offline address book (Send / Receive - Download address book) with no change.
Our help desk had me turn off Cache Exchange Mode and it works but I never
had to do this before. I'd like to get back to Cached mode so my junk email
filters will work. Anyone know how to get this working again?

Outlook 2003 SP3

Thanks.