The format which the videos are in aren't compatible with your mobile. You will have to convert said files into a format which is compatible to your phone. Such as Mp4 format, will work on the latest phones. as he said, you have to determine which types of video files your phone can play... check the manual, or check some of the sample video files that come with the phone or record a video and see which extensions the files use:    myvideo.3gp  myvideo.mp4    are common mobile formats...    then if you have let's say an .avi or .mpge video you'll have to convert it first in your computer using some converter software and then upload it to the phone and enjoy...