BF2 and SP3
 

I used successfully BF2 trainer (bf2_trainerx.dll) until I installed Windows Service Pack 3. Then the keys F5 and F6 did not work at all.
Back to Service Pack 2, and the trainer did work again (Ghost) .
Again back to SP3, and it did not work anymore.
(I use Batllefield 2 only as Singleplayer, and with Forgotten Hope 2, I die otherwise too quickly.)

So, SP3 does do something nasty here.
What can I do ?

This won't be the only software you'll have problems with under SP3. Keep SP2 for another few months...