We have tested and verified that the lesson videos play in Firefox, IE8, IE9 and Chrome on Windows XP and Windows7 as well as Firefox, Safari and Chrome on the Mac. We have also tested and verified that the videos play on the iPhone, iPad and Droid devices. We understand there can still be issues where the videos may not play as they should. If for some reason the videos do not play for you, make sure your flash player is up to date. If the videos still do not play, check your browser settings and browser plugin/extension settings to make sure nothing is set that may prevent the videos from playing. There have been cases where Windows7 users needed to update their graphic card drivers in order to play the videos, especially if they've updated from Windows XP. If you're using Chrome and the videos do not play, here's a little trick you can do that will usually fix the issue in Chrome. Type chrome://flags in the address bar and hit enter. Look for Disable hardware-accelerated video decode and click Enable. Make sure you click the Relaunch Now button at the bottom for the changes to take place. One way to test if the issue is browser specific is to try the lessons on a different browser. For example, if the videos do not play in Chrome, try it in Firefox or IE. If they play in the other browsers, then you know that the issue is with the settings in Chrome. If you have exhausted all options and you still can't get the videos to play, please feel free to contact us through the Support page.