Do not activate the trainer on the main menu. Load into gameplay—for example, Leon Chapter 1. Once you see your character and can move, pause the game.
A: Run the trainer as Administrator. Also, ensure you are using the correct version (e.g., latest Steam build vs. old Games for Windows Live build). Resident Evil 6 Trainer Unlock All Weapons
Using a trainer is generally a straightforward process, but following these steps will ensure you don't corrupt your save files. Do not activate the trainer on the main menu