The Microsoft Outlook 2010 MAPI Reference has been updated on MSDN! The updated documentation is also available as a download.

This release includes documentation for the binary stream structure for the PidLidPropertyDefinitionStream property. This property specifies definitions of all custom fields and data-binding settings for built-in fields of an Outlook item.

There is now a code sample in How to: Check the Version of Outlook that shows how to check version information of an installed version of Microsoft Outlook, if the installed version is Outlook 2010, Outlook 2007, or Outlook 2003. The code sample also returns a pointer to a Boolean variable that indicates whether a 64-bit version of Outlook is installed.

MAPI provider code samples for Outlook 2010 are also available at the Outlook 2010 MAPI Code Samples Web site. These code samples support 64-bit MAPI. The link in the Outlook 2010 MAPI Reference currently still points to the Outlook 2007 set of MAPI provider code samples, but will be updated the next time the documentation is refreshed on MSDN.