FOR WINDOWS 2008
In some situations, IPv6 can be an compatibility issue for certain applications running on Windows 2008. A quick way to completely disable IPv6 on Windows 2008 is to run the command below at cmd prompt [make sure you are loggedin as administrator] then reboot your server.
reg add hklm\system\currentcontrolset\services\tcpip6\parameters /v DisabledComponents /t REG_DWORD /d 4294967295
(I used it last day when I was migrating my Active Directory from 2003 to 2008)
FOR WINDOWS 7 x64
reg add hklm\system\currentcontrolset\services\tcpip6\parameters /v DisabledComponents /t REG_DWORD /d 255
Regard’s
Syed Jahanzaib