I have found a way to atleast bypass the temporary ban error but
only for like 3 seconds.I hope somebody can do something with this.
Its sorta like the PS3 way. But after 3 seconds it kicks you out and then you get the
temporary ban error. Its simple

1. Dashboard and sign out
2. unplug your network(offline) , And go to settings
3. Go to clock and change the year to 2010
4. start black ops 2 still offline and not signed in
5. Then when your in the multiplayer menu plug in your ethernet cable or wifi
6. Click xbox live and sign in, then it wont give you the temporary ban error
but only for 3 seconds then it would boot you off and give you the tempory ban error.




If any questions PM me.