Thank goodness for that internet thing. Because Mr. Kulov recorded his pain, I was able to recover from this issue quickly.
If a process already owns port 80 and you try to debug in Visual Studio where you are trying to use your local IIS installation, you will get this error. Like in Martin’s case, the offending application was Skype (which has an option in tools to use port 80 and 443, uncheck this) which was using the port. If you don’t have Skype installed or running, run netstat –b to find the application causing the issue.
Also, remember to restart your website after you resolve the issue.