I received this message when I tried to login this morning. First time it ever happened to me, never had any similar problems. Googled around a bit and then tried deleting the profile and recovering. Worked perfectly and I could log in, however after playing for around 30 minutes I got disconnected for no reason and when tried to log in again, received the same message: your live membership information is not valid bla bla.
I can login to my account on xbox.com just fine. Neither the email or the password are changed.
So...any idea what is going on?