There is one of three explanations for what you are seeing.
1.) Windows 98 machines with NICs setup for DHCP will automatically assign themselves IP addresses--just as bob stated.
2.) Your 98 machines may be leeching IPs off of ICS (Internet Connection Sharing) from one of the 98 machines. Check the Windows Setup tab in Add/Remove Programs to see if any of the 98 machines have ICS installed.
3.) Same as #2, but with the W2K Pro computer. The only real difference is that ICS will be found within the Network Properties for your NIC and/or modem connections.
On the bright side, your network is up and running...hehe
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Semper Fi,
L.G. Huber III, MCSE/MCP+I/A+/N+
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