You need a converter to do so. They need to be in the format to do on PSP. Erm... MP4 http://www.imtoo.com/psp-video-converter.html http://www.m2convert.com/psp-converter.htm http://www.pspxstudio.com/
Let me got my memory stick and find out... ONE SEC.. Merged Post: Just create a new folder in the root directory named MP_ROOT, and then make a folder called 100MNV01 in there. So your .MP4 files should go into E:\MP_ROOT\100MNV01, where E:\ is the drive letter of your Memory Stick. (The Root is When you get into the Memory Stick. DONT go into PSP folder)