There can be random errors introduced into hard disks files that some people attribute to cosmic rays. I know this sounds a bit conspiracy theory and though it is rare it does happen. Also hard disks do not last forever. So there is a possibility that one of your Mach3 files has been corrupted and so it may be worth renaming the current Mach3 folder something like oldmach3 and reinstalling Mach3 to see if that gets it to work again. If it does then it should be a case of copying over the configuration file, license file and part files and carrying on. If it does not work you can delete the new Mach3 folder and put the name of the oldmach3 folder back to Mach3. I personally keep a backup copy of my Mach3 folder on a separate machine and a USB stick just so I can replace it if I suspect the working one has been corrupted. If the parallel port is the fault then you may have to go down the route of either a USB port controller or a network port controller. I use laptops without issues having set them up to never shut down when external power is on, I think it was just a case of setting them up to act like a desktop.
Martin C
