Visual Studio 2013 C# Web Project builds but IDE reports The type or namespace name xxx could not be found error

Question

When opening an MVC4 C# web project in Visual Studio 2013, the IDE reports the error \"The type or namespace name \'_\' could not be found (are you missing a using

Answer 1

I had the same issue.

It's a VS 2012 solution with different projects.

Search for all *.suo files and deleted them. Rebuild and reopen Visual Studio.