Don't use F1, as that is universally the key for Help in Windows. Such shortcuts should pretty much always involve at least one modifier key and preferably multiple, to reduce the chance of a clash with a function of the application with focus. Regardless, you should look into the RegisterHotKey
API. That will enable you to register a hotkey with Windows, so you can notified when it is pressed even if your app doesn't have input focus. You should read the relevant documentation and you'll no doubt be able to find a number of examples of its use in C# on the web.