.mp4 (quicktime player format) codec not found

[d4mation]

hey, i am running Ringtone Media Studio V.2.20 and when I try to open a Quicktime player format file I am told I do not have the proper codec for the file. ALTHOUGH... I can open this file with RMS on my Desktop computer (I am currently on my laptop) but the desktop can't send files to my phone for some reason. I am trying to make a video file with the .mp4 quicktime format file in conjunction with a .wav audio file.

I was wondering if anyone could send me a link to a codec download that you know will work.

Thank you for your time.