I was trying to run the default website in a default installation of IIS on Vista, and I got this error message:
What the …? Who comes up with crap like this? Unbelievable… even the error code is useless to search for, as apparently there are hundreds of other error conditions in Windows that bring up the same error result. Does Windows have so many error conditions that the value range of a 4 byte uint is no longer large enough?
So what was the problem? Very simple: another application was already listening on ports 80 and 443 (Skype — does that by default, thank you very much). Apparently it’s really hard to have an error message like “Another application (Skype, PID: XXX) is already listening on port 80.”, or at least “Error trying to listen on port 80.” Well, it’s only IIS 7 — maybe they’ll get it right for version 22 or so.