I think it's because I'm running Windows 7 64 bit, because the only trainer that does work is the Crysis 64 bit trainer.

The trainers that won't operate are:
Arma
Arma 2
Medieval 2
Company of Heroes Opposing Fronts

Now, all of these are 100% up to date, Arma and Arma 2 I brought up to date myself, and Medieval 2 I bought as a "Gold" pack, with all the expansions, so shouldn't need any updating.

Company of Heroes, however, I bought as an "Anthology", and includes the opposing fronts and tales of valour expansions. It is up to date, but I don't know which trainer I should use for it. (ie regular COH trainer, TOV trainer of OF trainer)

Crysis trainer works perfectly.

I'm running all trainers as admin, and I've tried in XP SP2 compatability mode, for some of them, but what happens is this:

I run the trainer. Loads normally. I run the game. It loads normally. Pressing F1 does nothing, I don't hear any activated or anything, and presing corresponding keys to activate trainer functions do nothing. Game runs normally. Once I quit game, the trainer, in the background, is revealed to have "locked up" and requires the task manager to shut it down.

How do I get these trainers to work? Yes, they are the right versions for each game.

It's driving me crazy. Please help!

Link

This is because the CH trainers do work with the 64 bit OS'es.

Right version: Yes.
Third Party Apps: None running.
Antivirus: Off.
Read Instructions: Yes.
Copy protection: All legally bought, but only Medieval 2 has a no-cd patch applied, because there aren't no-cd patches available for the other game versions.
Multiplayer mode: Hell no.
Key mapping conflicts/multimedia keyboard: No, and no.
F lock/Num lock on: Yes, and yes.
Windows 7: Yes, and I've already tried a million different compatability variations.
Downloaded: Arma I got from Direct 2 Drive, all others I bought from EB Games.
Where I put the trainers: On desktop, and in the game directory. Neither worked.
Sound Card: Working perfectly.
Haxor trainers: No.
Tried running different ways: Yes, every way I can think of.

That covers the link, word for word.

He says no security applications are running?

I am not actually believing that since the problem he is getting is generally due to the trainer getting blocked.

Have you tried turning of UAC (@OP)

yes i know that i said something is still...