In ALL cases this is a FALSE ALARM as NONE of the Game Trainers @ GCW contain known malicious code! More info in the PC Games FAQ! If you have problems using a trainer in combination with Windows Vista, 7, 8 or 10 then make sure to run the trainer with Administrator rights and when needed in Windows XP or Windows 98 compatibility mode! The best place to get cheats, codes, cheat codes, walkthrough, guide, FAQ, unlockables, achievements, and secrets for Halo 5: Guardians for Xbox One. For Halo Wars on the Xbox 360, GameFAQs has 106 cheat codes and secrets.
Trainer troubleshooting: The most common problem getting a game trainer to work is compatibility between the trainer and the operating system version, if you are using an older game trainer and running Windows 7 or Windows 8 it simply won't work, if however, you right click the trainer and choose Properties and then Compatibility you can change this to run in Windows 98/ Windows 2000 etc. You can find more information on the Beginners Help page here