hi there i have a alienware 51 m15x laptop whit windows vista ultimate and i got a Matshit BD-MLT UJ-220 SATD DEVICE AND IT WILL NOT PLAY THE BLU-RAY MOVIE AND IT A BLU-RAY PLEASE HELP..
Megaman is correct.
Your laptop likely has a downloads section @ alienware as well where you could find driveres and original software which came with your laptop.