I found a fix. I don't know if it will help you but here's what I did.

I downloaded this to my C: drive:

http://download.windowsupdate.com/Wi...gent30-x86.exe

Clicked the start button, then run and typed this in:

C:\WindowsUpdateAgent30-x86.exe /wuforce

Then I went to windows update http://www.update.microsoft.com/wind....aspx?ln=en-us
and clicked the Express button. The red shield went away.

Hope this helps!
:)