I have two apps, one is a standalone WPF app and the other is an XBAP. Both use a common code base (shared project) to access Outlook data using COM Interop.

The WPF app runs fine and has no problem reading/writing Outlook data. The XBAP, running at the same time, always fails with this error:

Retrieving the COM class factory for component with CLSID {0006F03A-0000-0000-C000-000000000046} failed due to the following error: 80080005

So does this mean XBAPs can't use Interop? The XBAP is running as a full-trust application.