Hey guys. I've had this problem for the past three days. Before then, my Xbox LIVE worked perfectly.
The problem first started when I turned on my Xbox to play Halo 4 multiplayer. At this point, Xbox LIVE was still working for me. As soon as I got on, the game messaged me and said something along the lines of " Unable to write to your gamer profile." I went back to the dashboard and it turns out I was no longer logged into LIVE.
Obviously, I tried to sign in again but I received an error saying : "Your connection to Xbox LIVE has been lost. Please try again. [Ok] / [Test connection]". I tested my connection wondering if my internet had gone out only to find that all the connection tests passed. No issues whatsoever. I tried signing again and got the same error. Rinse and repeat.
If anyone can help me, it'll be greatly appreciated.