In Internet Explorer, in either the View or the Tools menu, find the "Internet Options" dialog box and open it. Click on the "Security" tab in this window. Make sure that your security setting for the Internet Zone is set to "Low" before installing the new codecs.

If you select "yes" to add a new codec, you must restart your system for the new codec to function properly. If you installed a new codec, but did not follow these instructions, you may now be having problems. If you are having problems after installing a new codec, please go to:

http://www.microsoft.com/windows/windowsmedia/en/default.asp

Simply download the software and install it. Once installation is complete, restart your system. You should then be able to see and hear all the music videos properly.