Unable to start debugging. The startup project could not be launched. VS2015

Question

I have started a new console project in VS2015. I only have this code :

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text         


        

Answer 1

I had this problem developing a react native app for windows in Visual Studio 2019. I started the debugger then stopped it in the terminal by using ctrl-C. I was not able to restart the debugger and the "start debugging" and "start without debugging" options were disabled in the debug dropdown. Restarting Visual Studio, etc, and some of the things described above did not work. Through hunting and testing, I noticed that if I switched views in the Solution Explorer to the MyProject.sln instead of the fileview, the debugging was enabled again. I'm not sure why, but it appears I need to be in the sln view to start the debugger.

Answer 2

The solution for me was to delete all *.user files that are normally generated for both solution and project files

Answer 3

I got this problem solved by clearing MEF component cache.

Use this VS Extension to clear cache very easily.!!

Answer 4

After upgrading MSVC2015 to Update3, I had the same problem: instead of std::map in the Watch window display as a horrible std::_Tree<std::_Tmap_traits... etc., some plugins started to throw exceptions, some projects was not able to run in debug mode.

All was solved by deleting CurrentSettings.vssettings. It is usually located at Documents\Visual Studio 2015\Settings If not, go to `Tools -> Options -> Environment -> Import and Export Settings ' to find the location of this file.

Answer 5

Delete all relevant /obj and /bin folders. Run again.

Answer 6

Additionally to "Unable to start debugging" I also had errors "The operation could not be completed: Unspecified error" when I tried to rebuild.
Thanks to Visual Studio popup: "the operation could not be completed" it was enough to close Visual Studio 2015 and then open again.