Visual Studio 2010 Designer Error on Run

Question

I am using using VS2010 and if I have a form open in designer mode and run my application the designer tab will no longer show the form designer but instead an error will be di

Answer 1

"In the project file (.vcxproj), locate the entry for the target Framework version. For example, if your project is designed to use the .NET Framework 4.5, locate v4.5 in the element of the element. "

(Microsoft)

In my case the "v4.5" didn't exist so I add it, and everything is good now.