Everynow and then one of my 360's gives me this message when press the Guide button. It happens online and off As you can see in the pic im on MW2 online , it dont stop me playing but i wanted to know what it is. Normal 360 non hd port I can't replicate it , it just happends once a month or so . Its not a big deal but maybe someone knows.
No idea what's happened there, the only time I have ever seen that is on the Xbox 360's that are usually in shops. If you look here: "The Xbox Guide is Not Available in Demo Mode" - Help! - Page 2 - Xbox 360 & Xbox Forums it can happen if you have your 360 connected to the TV using a splitter. Although that was posted over 4 years ago now!
I think it may be a display only xbox that you might have gotten. It must've had the demo f/w. Me thinks.
try using the xbox360 manual factor mode mod to reset it back to normal instead of demo mode need the link msg me back