I have a solution with 2 projects: MyC#Proj, MYCppProj.
Right click on solution->properties->Configuration: The two projects appear under all configurations and platforms. In Any CPU: MyC#Proj platform = Any CPU, MyCppProj platform = x64.
Click on Configuration Manager: e.g. Configuration Debug, platform Any CPU: MyC#Proj platform is Any CPU, MyCppProj platform is x64. Both are marked Build true.
Under "Change Source Control", both projects are binded, binding path looks good, connected, status valid.
Building solution on dev machine from clean folder, both projects are built successfully.
Building in TFS build, it seems MyCppProj isn't built: Looking in the Log File there is no mention of the project and also the expected x64 folder on the build server isn't created. MyC#Proj is built in Any CPU.