In order to use both AppleTalk and TCP/IP in the ARA 3.0 personal server, both protocols must be set to use the same interface (Ethernet, for example). If you set TCP/IP to Ethernet and set AppleTalk to the printer port, then you will get this error.
A common misconfiguration that causes this error is setting the TCP/IP control panel to configure via PPP. This will not work for the server; TCP/IP must be configured for the interface that AppleTalk is set to.
"Answering is Disabled. Default Client's IP Address is being used by another user. Enter another IP Address and try enabling Answering again.
This message comes up in two situations: