PMU problem

ok i get this error when i try to play

what can i do to stop it?

I think you need to download the “Microsoft .NET Framework 3.5 Service Pack 1” for it to recognize.
http://www.microsoft.com/downloads/details.aspx?FamilyID=ab99342f-5d1a-413d-8319-81da479ab0d7&displaylang=en