.REM File Extension
File TypeBlackBerry Encrypted Data File
What is a REM file?
File stored on a BlackBerry smartphone; may be one of several different file types, but uses an ".rem" extension to indicate the file has been encrypted; often has a compound file extension, such as ".jpg.rem," which would be an encrypted JPEG image file.
REM files can only be decrypted on a BlackBerry phone. You can turn off encryption by navigating to Options → Advanced → Media Card → Encrypt Media Files and then choosing "no." Once encryption is turned off, then you can transfer files to a computer and open them normally.
NOTE: REM files may be transferred to a computer using RIM's BlackBerry software, but cannot be opened directly on a Mac or PC.