Just sharing a workaround I provided to a question asked on the Microsoft Training and Certification forum in relation to launching a Self Test module in Microsoft E-Learning Course 6690 (Exploring the Fundamentals of Network Infrastructure in Windows Server 2008):

Q: When starting a "Self Test" or "Game", the popup notification or instructions with the "Ok" or "Start" box will NOT go away once clicked. It remains where it is placed directly over the test or game itself.

http://social.msdn.microsoft.com/Forums/en-AU/CertGeneral/thread/b2ef324f-9f26-4648-aa09-0a1b03000904

A: To fix this error you need to set microsoftelearning.com to be displayed in Internet Explorers Compatibility View mode:

1. Launch IE
2. Select the Tools menu option (ALT + T)
3. Select the Compatibility view settings menu option
4. Enter microsoftelearning.com in the Add this website field
5. Click on the Add button
6. Click on the close button

This workaround has been tested on IE8 and IE9.