At my company (RealDolmen) we use Microsoft OCS for internal communication. I’ve been using Office 2010 for a while now, and one of the things that bugged me is that the OCS client kept complaining about a required update (KB936864). This is a bit odd as this hotfix is for Outlook 2007 and is not applicable to Outlook 2010. After using my google skils I found the following TechNet thread:
http://social.technet.microsoft.com/Forums/en/ocsinterop/thread/1476cca6-5d30-4600-8ef7-80dca443d3ea

The above notification can be easily fixed with uninstalling the “Microsoft Office Access database engine 2007” software.