PR_MAPPING_SIGNATURE and custom message stores

posted by  mvrok (14)  15 months ago (blogs.msdn.com)

I was pulled into a neat little issue with a custom message store that didn't behave correctly with appointments in Outlook.  It seems that everything was created fine, and Outlook set all of the named properties correctly on appointments.  The custom store was supporting named properties correctly and exposing them in their contents tables, so Outlook was happy.  Different calendar views worked great.

However, things got weird once you started a new MAPI session.  For reasons specific to the custom store, it decided to change it's named property-to-proptag mappin