The NMMM file extension is related to a Samsung Memo backup file. These files are created by Samsung Kies or Samsung Smart Switch. There is no known program that can open NMMM files currently. Previously, Samsung apps allowed users to migrate notes from NMMM files to Samsung Notes. But they no longer support this format. When you double-click a file to open it, Windows checks the filename extension. If Windows recognizes the extension, it opens the file in the associated program. When Windows does not recognize an extension, you get a message to select an app to open the file. It means Windows does not have a default program for that file type.
Many people share .nmmm files without explaining how to use them. This makes it hard to determine which program can edit, convert or print these files. We created this page to offer help on handling .nmmm files. The nmm file extension relates to an old Microsoft program called 3D Movie Maker. Nmm files contain video created in 3D Movie Maker. This format was replaced with the 3MM format. 546 file types use the NMM extension but most are not compatible. You likely need different applications to handle each one. Nmm files were originally for the 3D Movie Maker app by Microsoft. Reading or modifying Microsoft 3D Movie Maker Video files is often done in 3D Movie Maker.
In most cases, the suggested programs should open NMM files. If none are listed, likely no NMM supporting program is installed. Install a program from the list that supports NMM files.
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