MFCMAPI

MFCMAPI provides access to MAPI stores to facilitate investigation of Exchange and Outlook issues and to provide developers with a sample for MAPI development.

MrMAPI is the companion command-line tool for MAPI diagnostics.

Caution: MFCMAPI can modify or permanently delete mailbox data. Back up important data and only make changes you understand.

Get MFCMAPI

Install with WinGet (recommended)

For 64-bit Outlook, install with WinGet:

winget install mfcmapi

For 32-bit Outlook, specify x86 instead:

winget install mfcmapi --architecture x86

After installation, launch MFCMapi from a new terminal.

To update an existing WinGet installation:

winget update mfcmapi

Which version do I need?

Match your Outlook installation, not Windows: use x64 for 64-bit Outlook or x86 for 32-bit Outlook. Check under File > Office Account > About Outlook.

Download portable ZIPs

Download the latest release and extract the appropriate archive:

Your Outlook	MFCMAPI archive
64-bit Outlook	`MFCMAPI.x64.exe.<version>.zip`
32-bit Outlook	`MFCMAPI.exe.<version>.zip`

Here, <version> is the release version. Run MFCMapi.exe from the extracted folder; no installer is required.

Looking for MrMAPI? Download it from the same release page: MrMAPI.x64.exe.<version>.zip for 64-bit Outlook or MrMAPI.exe.<version>.zip for 32-bit Outlook.

Matching PDB archives for debugging are also available on the release page. Match the release and architecture when downloading these files.

Dependencies

MAPI: Accessing profiles and mailboxes requires an installed MAPI implementation, normally supplied by classic Outlook. New Outlook for Windows does not supply classic Outlook’s MAPI implementation. Match MFCMAPI/MrMAPI’s architecture to the installed MAPI provider.
Visual C++ runtime: MFCMAPI and MrMAPI statically link their own C++ runtime, but Outlook’s MAPI DLLs can require the Microsoft Visual C++ Redistributable. If a missing runtime such as VCRUNTIME140_1.dll prevents MAPI from loading, install or repair the latest supported Visual C++ Redistributable matching Outlook’s architecture (x64 or x86), not just Windows. A missing dependency can cause a “module could not be found” error even when the MAPI DLL itself exists.

Help and feedback

For assistance using MFCMAPI, developing add-ins, or general MAPI development, consult the documentation. Find a bug? Need help? Have a suggestion? Report your issues through the issues tab.

Contributing

Interested in contributing? See Contributing for build requirements and development setup.