Am I mistaken that all other P.C are working fine connecting and that 1 particular P.C is having Problem connecting????So I would then say that the problem may be within that particular P.C. if im correct….
-Check for any recent changes of any I.P address on that P.C(if exist/required)..
-Could also try and uninstall Antivirus and check the contivity if it works..
-Check for any malware/Trojan/virus infiltration..
Ive had the exact same problem but with Window 7 Pro Laptop; check it out if of any interest..
Restting Winsock didnt work however installing Service Pack 1 update for Win 7 got me to connect via both Wireless and LAN..
Hope this helps..