Q: I just bought a Macbook and some of the videos that I used to be able to play on my Windows machine no longer work. I thought the Mac was the best for video. Any ideas? - Jason, via email. A: The problem you are probably having is that you don't have the proper Quicktime plug-ins to decode the videos. Mac OS X tries to use Quicktime to playback almost all of the video on your system. Since there are so many video formats, Quicktime doesn't support everything out of the box. To make it work, you need an extra plug-in to help it decode the formats it doesn't natively support. Here is what I would recommend. Whenever I install OS X, I always add a few Must have components. The first one is the Flip4Mac WMV plug-in. This is a 3rd party app from Microsoft that will decode most of the WMV formats ... including Windows Media up to version 9 , and various streaming formats. If you have ever gone to a website like CNN , and the video doesn't work, this plug-in will probably fix it. Note: Video or audio with WMV style DRM copy protection will not work. For most everything else, I recommend a program called 'Perian'. Its called the swiss army knife of quicktime components. With Perian, you can decode various AVI, DIVX, XVID, and a whole lot more... These are the two MUST have installs for ANY Mac user. Now, if you still can't get your video to playback, try a free program called VLC. That stands for Video Lan Client. This media player will almost ALWAYS playback anything you throw at it.