I've had this interesting problem with IIS7.
I have a number of HTTPS sites in IIS7. That hasn't been a problem, until I wanted to go and set up VisualSVN Server using an SSL certificate. The installer had trouble starting the service. When I looked in the event log, the error was that "the file is already in use by another process." I figured that the "file" was really a socket, and checked with netstat - even though IIS was only bound to three specific IP addresses (.160, .156, and .168) with port 443, it was consuming *:443.
I could stop the World Wide Web Publishing Service, start VisualSVN, and then start IIS, but then none of my SSL servers would start.
Any helpful hints about how I could make IIS not try to default-bind to *:443?