Migrating from MAPI
Topic Last Modified: 2007-03-21
MAPI is used to develop applications that access items and folders within public and private stores. MAPI is de-emphasized in Microsoft Exchange 2007 and has been replaced by Exchange Web Services.
Migrating from MAPI to Exchange Web Services
Exchange Web Services provides the same access to the Exchange store as does MAPI. Exchange Web Services provides extended properties that provide access to all of the same properties that MAPI can access.
The following are a few of the benefits of migrating from MAPI to Exchange Web Services:
- Using MAPI to write stable multithreaded code is often a challenge. Exchange Web Services code is relatively easy to make multithreaded, because there is much less state to be maintained.
- MAPI calls are granular, and, as a result, MAPI updates often take several round trips to the store. Exchange Web Services calls are chunked, so that very few updates take a second round trip. As a result, Exchange Web Services calls are typically more efficient.
- MAPI calls treat items in the store elements as property bags, while Exchange Web Services calls provide strongly typed objects, much like CDO 1.2.1.
You will eventually need to redesign applications that you created by using MAPI to use Exchange Web Services. Consider redesigning custom applications that were created by using MAPI as early as possible.
Note
The ExtendedFieldURI element provides access to MAPI from Exchange Web Services.