i dont kno about msn messenger i dont have msn...but i do have aol and was able to send cab files to my buddy who has a pro thru the aol account i set up on my phone...so i dont see why u couldnt with msn...just go into ur device or storage card where u have the cab u wanna send...tap and hold it until u see the pop up window...hit send and it will bring up optins on how u wanna send it...