Cannot find DNX process after updating Visual Studio 2015 from Update1 to Update 3

I had an asp.net RC 1 web site.  I always ran it using https (project properties > Debug > Set the address tohttps://localhost:12345.  Now I can no longer run the site as HTTPS as I get an error "Cannot find DNX process".  The exact error reads:  n error occurred while attempting to determine the process id of the DNX process hosting your application 

If I switch back to http://localhost:12345 it works fine and my code runs.  What am I doing wrong?

Thanks in advance!