Enabling teredo on Windows Vista and above

Linux users: install miredo and start it and you have IPv6. Optionally set server in /etc/miredo/miredo.conf .

The easy way

Create file called whatever.reg with this content:

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Dnscache\Parameters]
"AddrConfigControl"=dword:00000000

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\TCPIP\v6Transition]
"Teredo_DefaultQualified"="Enabled"
"Teredo_State"="Enterprise Client"
"Teredo_ServerName"="teredo.ipv6.microsoft.com"

Now double click it and answer Yes to UAC and warning about importing registry values. Now you can either reboot or update Group policy by opening cmd.exe and running

gpupdate /force
netsh interface teredo show state

teredo.ipv6.microsoft.com can be replaced with any other teredo server in the .reg file.

The hard way

netsh int ipv6 set teredo client teredo.trex.fi

Optional, sets Teredo server. The default one is provided by Microsoft, this isn't, but this is in Finland where I live.

route print

Scroll up and see what is number of teredo. It's near top.

netsh
interface ipv6
show teredo
add route ::/0 interface=XX

Replace XX with number from "route print".

exit

netsh interface teredo set state enterpriseclient

Optional IF YOUR COMPUTER ISN'T IN DOMAIN! Enterpriseclient can be replaced with server or default.

regedit

Browse to HKEY_LOCAL_MACHINE

and create a new DWORD (right click somewhere in the middle of window) and name it as "AddrConfigControl". It should have value 0 by default, if it doesn't, set the value as 0.