Preffer IPv4 over IPv6 in Windows

start-->run-->regedit

Navigate to:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip6\Parameters

Create a new 32bit Dword (this works for both x86 and x64 machines) and call it "DisabledComponents"

Right-click and select modify. Fill in the field with all F's.

Reboot.