I am having trouble watching some .avi files on my imac I have tried both quick time and real time players. Any suggestions? The files are on a external hard drive a freind is lending me. All of the other files on this drive I can access such as picture and audio files. But a couple of .avi files I can not view. When I try to play them the viewer will show the length of the file (say 10:23) and the timer will count when play is pushed but there is no audio of video. Thanks for the help T.S.