Windows 7: Windows expereince index needs to be refreshed problem

OK my OS is Windows 7 64-bit. When I right click on my computer and go into properties, it says that the Windows experience index needs to be refreshed.

So when I refresh it, after a couple of minutes, my screen goes blank. I wait for a couple of more minutes but my screen still stays blank. So I have to force shut my laptop.

How do I solve this problem?

Thanks.

Try this: The Windows Experience Index rating may inherit an incorrect value after you make a change to your computer's hardware configuration or you start Windows Vista for the first time

Thanks! I used method 4 and it worked!

Great.