When trying to debug a ASP.NET MVC app, the breakpoints in my controllers arent getting hit. When entering debug mode they just show an empty red circle with a warning trian
The following has worked for me most of the time when I had this problem:
Find where your projects dll cache is being held (usually in ASP.NET Temprorary Files). Then close VS, do an IISRESET /stop (if you're using IIS), delete all the files in dll cache. Do an IISRESET, start VS, open your project and rebuild it.