Halo 3 FAILED TO LOAD CONTENT problem?

[Pun]

I have had halo 3 for a while but i have been playing it with a MU
I decided to buy a hard drive (20G) but when i put in the hard drive it doesn't let me play anything (campaign, multiplayer, custom games, amd forge)
And this hard drive was also used
WHAT SHOULD I DO

 

[Chamaeleon]

do the troubleshooting procedure on your xbox 360 and then check if it works (try other games you have and see if they work-it could be HALO 3) -otherwise return that used HDD