For a while I had my 360 (the most recent version, less than a year old) hooked up on my family's big screen tv which has 1080p capabilities while I was sick, I was spending most of my time in the living room so that was the reason. Today when I went back into my room and attempted to hook it back up on my tv (which is only 1080i/720p) I went to turn on the system and got a screen that says the format is not supported. i know that the format is because I have had it hooked up to this tv many, many times. I then switched it into standard mode on the back of the xbox to see if that was working without switching the connection on the back of the tv and it worked. I figured I might need to go into the display settings on the xbox and then switch the output to 720p and it said to switch the switch on the back of the xbox to HD and so I did that to only get to the screen that said the format was not supported. I have actually had this problem before with my old xbox after I was over at a friends house and had it hooked up to his tv which was 1080p then hooking it up to my 720p tv, I figured maybe it was damaged during the transportation which led to me purchasing my current xbox and just using my old one for standard definition televisions. I want to figure this out this time after not being able to find anything on the internet so any help would be greatly appreciated.