.MMF File Extension

Yamaha SMAF sound file format created for mobile devices; commonly used for cell phone ring tones, but also supports the display of text and graphics; can be created from .WAV or .MID files using Yamaha SMAF Tools.

Addtional information about the SMAF format, as well as tools for creating and playing SMAF files, are available from Yamaha's SMAF Global website.

Mail message format used by the Windows NT Mail client; contains a collection of e-mail messages created or received with Windows NT Mail; located in the "C:\Winnt35\" directory and named "[username].mmf" by default.

NOTE: Outlook Express is not designed to read MMF files. However, you can import them into Microsoft Exchange as a Personal Information Store (.PST) files, then import the messages into Outlook Express.