I had this issue when I started my LC 475 web server and it was something to do with TCP/IP settings. Firstly, go into the TCP/IP control panel, and then select "User Mode..." from the Edit menu. In the window that appears select "Advanced" and click OK. An "Options..." button will appear in the TCP/IP panel. Click "Options...", make TCP/IP "Active" and deselect "Load only when needed". Close the control panel and restart.

This means that TCP/IP will activate when the Macintosh starts up and not when you open a network program such as Mac HTTP.

This should sort it, certainly it worked for me. I think it was Luddite who helped me with that a while ago.