Before you start this guide, please make sure that you are an administrator, or it WILL NOT WORK!
If you are using vista here is a guide that (should) make the trainer work for you:
1. Right click on the trainer and then click on properties.
2. Click on the compatibility tab
3. Check the box that says "Run as Administrator"
4. Check the box that says "Run this program in compatibility mode for:" and from the drop down menu below, select Windows XP Service pack 2.
5. Do the above for Most wanted as well.
6. Run the trainer.
7. Run the game.
8. Enjoy (if it worked...)
Hope this helps
From where do we use the safe mode?