telnet problems: part deux

I had this problem not to long ago and a simple winsock fix for xp worked, but not this time. I am on a domain with a t1 line and my office has a switch with 4 ports. The other 3 machines in the office connect to telnet just fine, but the 1 rebel machine wont. It connects to webpages and messengers just fine, but no telnet. I’ve ran numerous spyware and virus scans, reinstalled tcp/ip, winsock fix, and reconfigered the ports in my firewall. Any suggestions?