How do i convert MPEG files to 3GP or other file formats without downloading £20 software? (Read Desc Plz :))?

Question

I currently have a Xbox which reads files from the computer. However, for some reason it can't read MPEG video files, So i thought that it must accept some other format if the Xbox can't pick up on the videos stored in the file. So, i was wondering if you could convert the file to another format without having to download unsafe or software that costs money. If it might be for some other reason, please enlighten me on what it might be. Thanks in advance :).

Answer 1

For file conversions I always use  http://www.zamzar.com/ . Its an online based program. You don't need to download software and you can convert almost any format