we need more information
do you have both expansions, do you use mods,
did you take a look at what windows updates you gotten since it last worked?, etc
i just tried the trainer, yet again, and like Pwizard, it still works perfectly
have you tried uninstalling those, restarting, and tried the trainer again?, 99 % it won't make a difference, but i had a few windows updates myself that for some reason interfered with CH trainers
Did you accidently update IE past 9?
Tried deleting the trainer and redownload?
Do you have the 2 ''scrambled'' DLC's?, personally, i couldn't get the latest trainer to work untill i purchased those 2, seen a few others report the same
im headet out the door now, but hopefully others can chim in with additional troubleshooting suggestions