Just make sure both machines are sitting in the same subnet with the same IP range and in the same workgroup/domain.
Also, make sure the Win98 machine has NetBIOS and TCP/IP running. You most likely wont need any other protocols.
Not quite sure what you mean by "router main pc"?!
Does that mean you have a router and a main PC or is your main PC acting as a router?
What type of switching are you using? Router have its own switch built in?!
Answer those mate and i'll help ya further.
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