Unable To Launch Web Server

Question

I have asp.net web application project in visual studio 2012. When I want to start it, I have the following error:

Unable to launch the IIS Express Web server: P

Answer 1

Killing the IIS Express Worker Process solves this for me; I run into this while trying to debug two concurrent instances of Visual Studio 2015 and switching between the two web solutions.

If this is a constant problem then Kedar's answer of modifying the solution is better, but in a pinch, for a code review, etc I prefer this.