Some users had been getting an error after updating to Windows 8.1 that reads "Secure Boot isn't configured correctly." This appears on the desktop as a watermark, and is one of the more common errors encountered when upgrading to the new OS. Microsoft thought that users should check to see if Secure Boot has been disabled in the BIOS, and if so, then re-enable it. If that doesn't work, then reset the BIOS back to factory settings, or if that doesn't even work, reset the PC back to its original factory state and then re-enable Secure Boot.
Chipzilla has come up with a better way. All you need to do is reboot enter into the BIOS mode, and access the secure boot options menu. Enable secure boot (if disabled), check on the option that says "Install Intel platform key," press F10 to save the changes and restart the system.
Of course, that doesn't solve the issue for those who don't see a Secure Boot option. They might need to update their BIOS first.