Visual Studio 2010 error: “Project Target Framework Not Installed” when opening a .NET 4.0 project

Question

I am experiencing a rather disconcerting issue with one of my development machines that I hope someone can advise me on.

I have a large Visual Studio 2010 VB solutio

Answer 1

update or reinstall the framework in question. run visual studio setup. click restore to defaults. will find all installed frameworks and not modify or remove plugins or liscenses. Even kept my settings.