When you upgrade a solution to VS2010 it has the nasty trick of upgrading all test projects to .Net 4.0
This has the minor side effect of breaking builds in most older projects. The following links describe the problem and the manual workaround.
Random outpourings of a software developer
When you upgrade a solution to VS2010 it has the nasty trick of upgrading all test projects to .Net 4.0
This has the minor side effect of breaking builds in most older projects. The following links describe the problem and the manual workaround.