On Windows 2003 server, I kept getting the message:  Unable to read configuration for Microsoft Internet Information Server.  After a bit of research and checked and found that the "Microsoft SharePoint Administration" site was stopped.  After starting it this message went away.

If the sharepoint site is running and you are still receiving the error, you might check the event log as it will sometimes write a message there if it is a problem with your virtual root or something like that.