IMAPIClientShutdown : IUnknown

Office 2013 and later

Last modified: July 23, 2011

Applies to: Outlook

Enables a MAPI client to carry out fast shutdown of the client process.

Header file:


Exposed by:

IMAPISession object

Implemented by:

MAPI subsystem

Called by:

MAPI client

Interface identifier:


Pointer type:



Queries the MAPI subsystem for fast shutdown support that is provided by loaded MAPI providers.


Indicates the intention of the MAPI client to proceed with shut down.


Indicates the intention of the MAPI client to exit the client process immediately.

The purpose of fast shutdown is to allow a MAPI client and any loaded MAPI provider with which the MAPI client has an active MAPI session to save MAPI settings and data. This enables the MAPI client to disconnect all external references and exit without causing any data loss. A MAPI client that needs to perform fast shutdown must use the IMAPIClientShutdown interface. The MAPI client can obtain a pointer to this interface by calling the IUnknown::QueryInterface method on any IMAPISession object.

A MAPI client always initiates a fast shutdown by calling the IMAPIClientShutdown::QueryFastShutdown method. The MAPI subsystem responds to the MAPI client's query by verifying whether loaded MAPI providers support the client's fast shutdown. The administrator can use Windows registry settings to help determine the level of provider support that is necessary for MAPI clients to proceed with fast shutdown. For more information, see Fast Shutdown User Options.

To proceed with fast shutdown, the client calls the IMAPIClientShutdown::NotifyProcessShutdown method to indicate to the MAPI subsystem the intention to shut down. The client then calls the IMAPIClientShutdown::DoFastShutdown method to indicate that the client process is exiting immediately.

For more information about fast shutdown, see Fast Shutdown Overview. For information about how to perform fast shutdown successfully, see Best Practices for Fast Shutdown.