MENC File Extension - Open .MENC File (Windows Mobile Encrypted File)

An encrypted file format that is used by Microsoft mobile devices. This file format allows files that were previously unencrypted to be encrypted by the operating system and then stored on an external memory card and safely transferred.

Encrypting the files will result in multiple files-- usually an encrypted version of the original in the format "file name"..menc. The GUID is used by the decryption program, possibly as a key to part of the decryption, so changing it can prevent a file from being decrypted.