How to disable System service from listening on port 80 in Windows Server 2003

Solution 1:

In W2K3, the kernel-mode driver HTTP.SYS listens for incoming HTTP and HTTPS connection attempts. You can configure the binding behaviour with the httpcfg.exe set iplisten -i x.x.x.x:y command. Have a look at some usage examples and the syntax and you'll figure it out.

Solution 2:

The IIS Admin service wouldn't be installed if the World Wide Web Publishing service wasn't also installed, so that's my guess as to what's listening on port 80. Have you checked to see if the World Wide Web Publishing service is running? You'll probably find that it is. You'll need to stop it or configure the default web site (and any other web site) to listen on a port other than 80.