Can't get port 6000 to redisplay x11

I have Exceed 2006 installed on an IBM Thinkpad laptop and the application works for everything but the xterm redisplay back from a unix server. I have turned off the Windows firewall, added the Xwindows to the exception list on the Windows firewall and checked that I'm at full duplex. It works on my desktop and I tested it on other laptops and they work properly. I have Windows XP SP2. I was asked to encrpyt the harddrive but others have done the same and their laptop still works for xterm. I've installed Ehtereal to diagnose the problem, but can't pin point why it is not redisplaying the unix login xdisplay. Does anyone have any suggestions on how to troubleshoot this problem?