I have had this issue since XBOX UK originally went down in Europe last year.
I have issues with my gamertag. I am unable to connect to XBOX live sometimes. I occasionally get a 'corrupt profile' message when checking System Settings > Profiles.
I have been able to resolve this temporarily at times by deleting the gamer profile and clearing the cache. I then re-download the profile and the gamertag works temporarily as a fix.
However the XBOX then plays up again as the gamertag picture (when pressing home) shows no picture. I also turn on the XBOX sometimes to see that my name is there, but I am a hollowed out shadow with 0 gamerpoints.
My XBOX 360 is legit, and I haven't modified or hacked it in anyway whatsoever. I am also a gold subsciber.
Can I get some advice please? I really don't want to lose DLC that I have paid for.