Rayquaza Master: That has absolutelty nothing to do with codes and is not the, nor ever was, the topic at hand.
Mewtwo87: No idea. Ask those at GS.com
Jerome: What do you mean? Do you mean you can't use Pokemon you've recieved in a trade or you cannot trade Pokemon? I've used the AR myself an I ahve never had any problems with it.
If you cannot trade Pokemon, then make sure you have the proper game link cable. You need a GBA Link cable. Old GBC and GBP, etc. will not work with the GBA. Also, you cannot trade with GSC or RBY games. Only RS game packs. If you have met all of those above, make sure the GBA cable is actually working and...that you are talking to the crrect person in the Pokemon Center.
If you can't use traded Pokemon, chances are you entered a code incorrectly and it has caused defects. I've had a problem with this once; Used a code with one incorrect digit, and while the code did work, my PokeDex no longer worked. You can attempt to fix this by saving the game with ALL codes off (heck, save the game without the AR plugged in). Then open up the AR, fix the code, check if everything's fine, then use the code.
Another solution could be that your AR is not up-to-date. Connect your AR to your PC, open up the AR program, then click the 'update' button. Refer to the cheat devices section of the FAQ for more information on updating.
And welcome to the PC. I hope you enjoy your stay here Jerome.