Hey people

Ive had a modded xbox for about a year now and just today i turned it on and the dashboard has changed. There is now no launch dvd, launch menu, or skins options on my xbox which means i cannot access my games or anything else on my xbox. What does come up is MS Dashboard - which doesnt open, Reboot, power off, settings, backup and flash bios. I was wondering if anyone knew what the problem may be? is my xbox F#!*ed or does this happen from time to time with these things? Any help on fixing this problem would be great.