You simply cannot use the parallel port driver on 64-bit Windows. You must use an external motion controller if you want a 64-bit OS.
The most significant change in 3.043.066 is the revised parallel port driver ( Mach3.sys ). Previous builds would occasionally lose the pulse train during heavy GUI redraws. Version 3.043.066 prioritizes the real-time thread, ensuring that step/direction signals remain consistent even when the Windows UI stutters. mach3 version 3.043.066
: Mach4 offers better multi-threading and modern UI, but it requires a paid upgrade and learning a new Lua-based macro language. Stick with 3.043.066 if you need a "fire-and-forget" solution for a legacy machine. You simply cannot use the parallel port driver