Can't attach debugger in an old project

Running VS2013 community and SDK2016 PR1 I have a problem to attach the debuger. This project was working perfectly with the previous SDK. What can I do except rebuilding the solution from scratch…?

May sound obvious but did you check Set as StartUp Project?


It may not!!! :wall: Thank you :-[

No embarrassment. I do this all the time too. I have found that whenever you upgrade a project (VS2013 ->> VS2015) it always needs to be done.