double clicking Visual Studio 2008 compilation errors does not take me to source file

Question

Today, I compiled the Telerik RadControls ASP.NET AJAX "Live Demos" project (which I compiled several times last week and worked) in Visual Studio 2008. I made some unique changes to the solution because our company doesn't use Visual Studio 2010, yet. See the link below for the changes I made.

Telerik "Live Demos" solution - connection strings & database setup

When I tried to compile it, I first got three errors that are shown below under compilation #1 errors. When I double click those errors, it doesn't take me to the source file. ??? I then purposely changed some code in a random file to cause a 4th compilation error so I could see what columns are normally populated in a compilation error. That's my compilation #2 errors. Then I fixed that problem I purposely put in, and recompiled again, and got the compilation #3 errors. Notice the slight error visual differences even though they are the same line numbers. Again, in the #3 errors, when I double click them, it doesn't take me to the source files. I'll try getting out of Visual Studio 2008 and going back in... perhaps this is a memory issue with Visual Studio left open untouched for 3 days over the weekend. If that solves, I'll post that as the answer, and we'll call it a Microsoft fluke.

FYI: "recompiled" meaning "Rebuild Solution"

Compilation #1 errors:

Compilation #2 errors:

Compilation #3 errors: