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