Error while trying to run project: unable to start debugging on the web server

So im at work, you know working. I checkout a project I need to fix a bug in and make it the default web site in IIS. I set a breakpoint and try to run the debugger.

Error while trying to run project: unable to start debugging on the web server

The fix wasn't too hard but it was kind of annoying. I have two versions of .Net installed on my work computer; 2.0 and 1.1.4blah. The default website was set as 2.0 when the project is actually 1.1.4 project.

What to do?

  1. Open up ISS and and right click on the website folder that host your site, in my case it was "deafult website".
  2. Choose the ASP.Net tab.
  3. One of the options is ASP.NET version. Change it to the correct version.
  4. Hit OK
  5. It should work now.

Asp.net tab in ISS