I found this quote from googling your problem:
"For System.FormatException, it is thrown when the format of an argument does not meet the parameter specifications of the invoked method.
For more information, please check:
http://msdn.microsoft.com/en-us/library/system.formatexception.aspxHowever, to narrow down the possible cause of corrupted .NET Framework, we can try Verification tool to verify .NET Frameworks on your machine.
Are you going to doing JIT debugging?
If not,, you can just simply turn off this feature.
Please see: How to: Enable/Disable Just-In-Time Debugging"
I dont know much about all of this .NET framework stuff so your going to have to put your googling skills to the test if this doesnt help you.