Designer can't be loaded in visual studio 2012

Question

I'm having exception while loading App.xaml designers:
System.Security.SecurityException
Designer could not be started because of a permissions issue on the drive to which it is installed. Please check the permissions of the folder before trying to start the designer.
Also , run as Admin didn't work .
Please Help me !

Answer 1

Have you installed latest update(update 4) for VS 2012 and still see this issue?

http://www.microsoft.com/en-us/download/details.aspx?id=39305

Answer 2

I installed the update 4 but it doesn't work. I still encountering the same problem