Will Mach3 work on windows 8.1

Yes, you can use Mach3 CNC motion control software with Windows 8, but you will not be able to access the parallel port with this version of Windows and Mach3. If you wish to use Windows 8 and Mach3 together, you will need to use a USB motion controller like the one shown at the following URL: https://www.buildyourcnc.com/item/electronicsAndMotors-electronic-component-breakout-Mach3-USB-Board