Simply a matter of color coding, hehe. The cable going to my primary machine is black, the cables going to the router and my server are both white, and virtually identical. It never even crossed my mind until I went to disconnect the router from the hub to see if that made a difference in the other machines being able to see each other, and when I yanked on the supposed router cable, the server moved...that's when I realized it

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The funny thing is, I fooled with the TCP/IP settings in both machines and the DHCP settings in the router for two days before I actually looked at the hub and saw the problem right before my eyes. Blargh...
Xayd