IIS will not start when using WorldClient on port 80

On a machine with multiple IP address and WorldClient running on port 80, IIS will not start.

This problem usually occurs when the following are true:

  • Your machine has multiple IP address.
  • WorldClient is set to bind to a specific IP.
  • When IIS tries to start it attempts to bind to all of the IPs on the server.

Check the following:

  1. Try to telnet to both IPs on port 80. This is done from a command prompt by typing: telnet 80 (replace with each IP, also note the space after the IP, before 80).

    If WorldClient answers on all the IPs, then you do not have the binding setup. Check your configuration in MDaemon under Setup | WorldClient | Web Server Tab. Verify the correct information is listed in the box under “Bind WorldClient’s web server to these IPs only” box.

  2. If the correct information is listed here, then IIS may be trying to bind to more than one IP, which will cause a conflict. Please try the following KB articles from Microsoft’s support site. They list how to setup IIS to only bind to one IP. You can also find information on how to contact Microsoft support by following either link: