Computer:
Windows 7. 64 bit.
Mach3 is installed with working parallel port.

Parallel port testing shows that input signals and output signals are present, but something keeps happening to prevent the CNC Device from receiving the signals from Mach3.

I'm suspecting that there is something wrong between the computer and the CNC Device OR there is something wrong with the Mach3 settings that it doesn't function.
All the wire connections in the CNC device are set [motors step, etc] correctly; i.e. there is power flowing through the system. Mach3 cannot send orders to the device.

Mach3 driver will not work with a 64bit operating system. If you want to use a 64bit OS then you need to use one of the many external controllers.
Hood

Hey so I've swapped to a 32 bit OS [had them in stock, rapid switch over] but the same problem persists. What could be wrong?

Mach 3 will run on a 64 bit system if you use XP compatible mode. Been there done it. 

GTMach3

Attach your xml and I will take a look.

geh7552
Mach3 runs no problem with a 64bit OS but if you are saying you can run the parallel port driver with a 64bit OS then that is news to me.

Hood