I'd like to share what problem we encountered during migrating a WinForms solution from .net 2.0 to 4.0.
It's important to underline that most of our projects have targeted to framework 4.0 already, but some executables still point to framework 2.0 due to some reasons
beyond our control. We would like not to demand both frameworks be installed side by side, just latest. For each net 2.0 project there was a configuration file created (app.config) with the following content: