Hi, Compositecrafters
Have you tried the "driver test" in C:\Mach3 folder, Let it run till it closes on it's own, Then re-boot and try Mach again.
You might need to remove "Mach3 Driver" in Device Manager, Right Click on it and Delete, then run the driver test again, It will re-install then run driver test as above one more time.
To get there Window's, Start, Control Panel, System, Hardware, Device Manager, Then MachX Pulsing Engines.
Hope this Helps, Chip