I installed VS.2017 Enterprise and start a web performance project. When I try to add a Web performance test to the project I receive the error:
"The Web test could not be loaded: Could not load the type 'Microsoft.VisualStudio.TestTools.WebTesting.SharepointInformation' from assembly 'Microsoft.VisualStudio.QualityTools.WebTestFramework' Version=10.0.0.0, .."
The above answer is correct but the problem is the directory isn't accessible in my case due to some reasons so I just open my cmd and run this command. Just run, it will copy the file, but first turn of the vs.
copy "C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\Common7\IDE\ReferenceAssemblies\v4.0\Microsoft.VisualStudio.QualityTools.WebTestFramework.dll" "C:\windows\assembly\GAC_MSIL\Microsoft.VisualStudio.QualityTools.WebTestFramework\10.0.0.0__b03f5f7f11d50a3a"