I've checked all the parallel port options and I've set the parallel port bios setting to be SPP (the other options were EPP, ECP and EPP+ECP). When set on SPP I get the not connected error. When set on EPP+ECP I get a flatline zero reading (while I am feeding a periodic test signal into it). I have modified the .ini file and I'm not using any adapters. Any suggestions, particularly on which adapters to use?
Usually if you are using a version of Windows from 2000 or higher then you will need the adaptor. This is not always true but usually is. I recommend trying the adaptor with the patch in the win.ini and seeing if it helps - it will not damage the computer or hardware at all if you use it when you don't need to.