I wanna convert my photo menc format to jpeg format what should i do?

Actually, .menc file (Microsoft windows mobile encrypted file) isn't a real file type extension, it only indicates that the file is encrypted on a Storage Device (windows mobile) where Storage Card Encryption feature is installed.... They can't be directly converted to Jpeg. You have to remove the encryption and then restore them to normal jpeg file. First transfer the files to the computer, and then disable the Storage Card Encryption from the Mobile/Device and again transfer back to the device.
More details with illustrations here (click here).

Good luck.

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