Removing build number?

I put Windows 8 back on yesterday, and the build number was not on the bottom right.
However, today I installed Media Center, and now I see Windows 8 Pro with Media Center Build 9200. Why did this all of a sudden appear? How do I remove it?

Only appears for a few moments after installing media center here.. Then goes away forever from the desktop here.

You need to activate windows with your product key.