I just built a cnc router and I'm having some problems that I just cant figure out. I bought a package off eBay from China (www.longs-motor.com) for all the electronics, it was a 4 axis setup, Nema 34 motors, DM860A drivers, and a breakout board. Using a old emachine cpu, XP, 1ghz ram, on mother board printer port.
So here is the problem. Last night I hooked everything up and went through the setup process and had it cutting circles and getting ready to set the backlash comp up, and decided to wait till today to finish. Went out this morning and started the machine up..... got Z axis, got X axis, no Y.... what the heck... so I checked the ports and pins setting, then switched drivers to a spare one, got movement in the -Y direction when jogging -Y and +Y. So then I thought maybe the BOB, wires, or port is bad. Pulled out the trusty Multimeter and went to checking pins. Everything from the computer, cable, to the BOB looked fine..... The BOB must be bad and fried the driver..... I better stop before I fry my spare driver..... So I ordered two breakout boards (1 spare) and another spare driver....  Went to movies and messed around but still was baffled how one day it worked and the next it didn't (this is new stuff).. So I did some more checking. Took the Y axis motor and hooked it to the X driver and the motor worked fine. "Good the motors not bad"   So then I hooked the X axis Puls and Dir wires to the Y driver that only moved one way (spare driver)..... Still only moves one way "Bad driver"    OK Lets hook the original Y axis step driver to the X axis Motor and Puls and dir and power... Nothing .........  a few choice wards about china and so on 
So this is my question, whats the chances of getting one bad step driver (the one that moved only one direction), and a Breakout board going bad frying a step driver ( original step driver). Or is there something I'm missing here... 

Had the same problems and as a fact still have the same problem until I reinstalled Mach3 from the ground up.
The first BOB was China made nuff said! Got a BOB and drivers from Probotix.com and talked with a live person too!
While Mach3 is killing my inner calm and I an=m too busy to have time on my cnc project.
the USA companies seem better and at a lower cost!!. Probotix is actually cheaper than the China junk I started with.
Bob

jut put together a cnc mill and when I turned it on for the first time the motors engage however I have no motor movement using an ebay 5 axis breakout board and m335 stepper controlers followed the tutorial on utube no joy all settings in mach 3 look correct still no movement, any help would be appreciated.

also the DROs move and I have been using Mach 3 without the mill for months testing g-cods and running simulations.