I had a Visual Studio web project that was configured to use IIS Express on port 8080. That should normally be fine and IIS Express is supposed to be able to run without administrator privileges, but when I would try to run the app I would get this error:
Unable to launch the IIS Express Web server.
Failed to register URL "http://localhost:8080/" for site "MySite" application "/". Error description: Access is denied. (0x80070005).
Launching Visual Studio with administrator credentials would cause it to be able to run the application successfully, but that kind of defeated the purpose of using IIS Express in the first place.
It turns out that the problem in my case was that something else had previously created a URL reservation for port http://localhost:8080/. I have no idea what did it, but running this command in Powershell showed the culprit:
[C:\Users\Eric] 5/3/2012 2:39 PM
14> netsh http show urlacl | select-string "8080"
Reserved URL : http://+:8080/
The solution was to run this command in an elevated shell:
[C:\Users\Eric] 5/3/2012 2:39 PM
2> netsh http delete urlacl http://+:8080/
URL reservation successfully deleted
Now I can run my web app from VS without elevation.