Hi all I'm new to cnc machining and have only done 2 simple carvings.  I'm using a Gatton cnc machine with a g3 controller and running mach3 on a windows 10 laptop.

My problem is I can zero the machine to the left front of the table and jog anywhere on the table and hit go to zero and the machine will return to the homed position.  However when I put the machine in work coordinates and zero for my cut after I run a code and put the machine in machine coordinates and hit go to zero the x and y axis do not move.  The z axis will travel up to the soft limit and then back to the part zero.  When I shut the whole system down and restart mach3 machine has to be reset.  I'm thinking I may have a corrupt file in mach3.  Any advise would be helpful.  Thanks in advance.

GoTo Zero always places machine to the 0, 0, 0 Work coordinates.
When you home the machine, you are establishing reference point for Mach to be able to orientate itself on the machine.
Work coordinates 0, 0, 0 are just that, work coordinates, and you establish them zeroing your X, Y and Z at the material origin.
When you shut down the system, and restart it again, it is normal for Mach to ask for a reset as the program has no idea where your machine is positioned.
So, no corrupted files, just regular behavior of controller software aka Mach3

Thanks for the reply.  One more quick question is there a difference between mach3 loader and mach3 mill?  I have been using mach3 loader.