|There is no need for a firewall between two directly connected pcs so disabling it eliminates one source of disconnect.|
If the firewall is off on both and you have a crossover cable the only reason I can think of for failure is a bad nic or cable or there is another product installed that also acts as a firewall. Norton is a common one.
To make sure tcp/ip is working ping 127.0.0.1 on each pc. Then ping its own ip address. Pings should all be successful.
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