This article explains what an MNY file is and how to open or convert it on your computer.
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A file with the MNY file extension is used with the now-discontinued Microsoft Money financial software. The program can store financial statements for checking, savings, and investment accounts, allowing multiple account details to be contained in a single file.
Microsoft's finance app also uses files with the .MBF (My Money Backup) extension, but that is used to indicate that the file is an MNY file that has been backed up for archival purposes.
Microsoft Money was discontinued in 2009, but you can still open your MNY files with Money Plus Sunset, Microsoft's own replacement for the program that not only supports this format, but also similar formats such as MNE, BAK, M1, MN, MBF, and CEK.