Some driver installation packages may require you to disable driver signature enforcement in Windows 8.1, which will allow unsigned driver packages to be installed on your system.
Note: Before you continue, save any open documents and close all open programs.
To disable driver signature enforcement, complete the following:
When your system finishes restarting, complete the following:
When your computer restarts, driver signature enforcement will be disabled and you can install your drivers.
Note: When you restart your computer after you install your drivers, driver signature enforcement will be enabled again. This does not prevent your newly installed drivers from working, but does prevent any other unsigned drivers from being installed until driver signature enforcement is disabled.