I had an issue today where I was trying to debug a console application but Visual Studio would not break at the breakpoints I set. I asked a co-worker to open the project on his workstation and in fact debugging worked for him under VS2015 so I knew it was something local to my installation. After trying various things I stumbled across this stack overflow link which solved the issue:
The setting in question is a Visual Studio setting and not one that is project or solution specific. The "Enable Just My Code" setting needed to be unchecked. It is located at:
After unchecking this setting my breakpoints began working again.