I have just installed the SMC my computer and I cannot convert video files. When I click on the file I want to add it says: This file, E:\VIDEO_TS\VTS_01_0.VOB, cannot be imported, please install the correct codec first. If the files can playback on your computer, probably Sansa Media Convert does not support this format, or the file is corrupted. What does this mean? What is a codec and how can I install it? What should I do to make the video files the right kind so I can convert them?