What version of windows are you running?(Vista/Windows 7 or Windows XP)
If you're running Windows XP, do this:
1 - Download this program:
WinSockFix2 - Run the program you have just downloaded. (WinSockFix)
3 - Click the button named "Fix".
4 - Restart your computer.
If you're running Windows Vista/Windows 7, do this:
1 - Press this key combination: Windows Key + R. (Windows key is usualy found in between the "ALT-key" and the "CTRL-key"
2 - Type in "cmd", DO NOT PRESS ENTER, instead press CTRL + SHIFT + ENTER. (This will run cmd in admin mode)
3 - Type in "netsh winsock reset"
4 - Restart your computer.
I wish you the best of luck.