Unable to start debugging verify debug settings for startup project VS2015 [duplicate]

Question

This message keeps showing when i press debug.

How do i fix it so i can debug.

I have had the project for a couple of weeks so its not new and it has been working normally.

Im running Visual Studio 2015 Enterprise as shown in title

Here is the message:

Answer 1

Restart Visual studio this is all i did and it worked fine.