Finally found an answer! After making a copy of the entire individual project on each machine and doing a file diff comparison of them, noticed a number of orphaned files on my machine in the obj folders. So went through all the projects in the Visual Studio solution and deleted all files in the \solution\project\obj\Debug and \solution\project\obj\Release folders. After doing a new build on the solution, it worked perfectly on my machine right away without any changes to app.config or anything else in the entire solution.