Open CMD, Reset WINSOCK entries to installation defaults by typing: netsh winsock reset catalog
Reset TCP/IP stack to installation defaults by typing: netsh int ip reset reset.log
Restart your PC.
If it doesn't work, download Winsock XP Fix from here, save it to your Desktop.http://www.snapfiles.com/get/winsockxpfix.html
Double click on the exe on your Desktop.
Press the "Fix" button, then restart again.
See if you can connect now.