What do you mean?
Have you bought it for your game boy or do you use VBA?
If you use VBA you need to go the the third menu named "Cheats". In there, select "Cheat list". Then if you got a GameShark code, press the "Gameshark" button. If it's a codebreaker, press the "Codebreaker" button ect.
EDIT! Just found another answer. I haven't actually read it but might be useful. http://wiki.answers.com/Q/How_do_you_add_a_game_in_action_replay
u cant
Yes
u put the game in the opening in ur action replay i think
well at the very top where the names of the games are listed there should be an add button. CrIsTaL:D
Some games are not compatible with the Action Replay, thus not letting newer games use the device.
i wish that i knew too if you find out email me....cdias1995@yahoo.com
Install the Action Replay software on your PCRun the Action Replay ProgramConnect your Action Replay to your PC via USBDownload a new cheats file and add it to your Action Replay.
It wont because they had to be games that have actual cheats.
OK first you need to have the game entered into the action replay then you go to the games screen by inserting the game into the action replay then add the codes name and code into the action replay if you want to find the code look it up on the computer
Go into the games screen and select "Add a game".
I don't have one but you can look them up or i think play the game with the action replay and it gets added.
Action Replay is a hacking device for video games that allows you to add, make, and share codes for thousands of games on a bunch of consoles, including Nintendo DS and Nintendo DSi.