The error is probably coming from some software you have installed that uses Outlook. We don't know what you might have installed.
You may be able to fix it by rerunning OUltook setup and making sure that the Collaboration Data Objects component is installed, but my guess is that in the end, you'll have to track down the people who made whatever software it is and ask them.
--
Sue Mosher, Outlook MVP
Author of Configuring Microsoft Outlook 2003
and Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers