small call of duty mw2 question

my cousin accidentally locked the russian mission on mw2.... and he also chose for the message not to be shown again... Just wondering where he would look to re-enable the mission

I'm not sure. Best guess would either to look in the options menu, or online :/ sorry.

take the disc out of the xbox and snap it in half is what ur gonna wanna do brah

The only thing I can think of is to delete the game from your HD. Then reboot it up, and it should ask you again. You'll lose whatever progress you've made to your Campaign though.

I don't think you can without deleting your save file, all though there might be an option for it, I haven't checked recently.