extruder not working on sprinter/pronterface or repetier with ramps 1.4 (no replies)

Here are some troubleshooting steps I took.
As far as I can tell, all the hardware is working perfectly.

Currently, all my hardware works, X,Y,Z, heatbed, extruder.

My issue is that extruder will not extrude forward or reverse when hitting the pronterface extrude button. Same thing I've observed on Repetier firmware with Repetier host.

Step 1: I switched out the stepper motor cable and the stepper driver with another axis.
Verified it is working.

Step 2: Reinstalled the motor cable and stepper back in extruder E0 slot on RAMPS 1.4 board. Edit pins.h on sprinter and replace the E axis pin value with one of the axis
/* #define E_STEP_PIN 26
#define E_DIR_PIN 28
#define E_ENABLE_PIN 24
*/

#define X_STEP_PIN 26
#define X_DIR_PIN 28
#define X_ENABLE_PIN 24

Hitting x-axis on pronterface moves the extruder.

Step 4: Enable the hotbed, extruder heater to 60 and 210 respectively and try to move the extruder on the pronterface. Still no go.

Step 5: Load repetier firmware and repetier host and test for extruder. Same thing, I can move X,Y,Z but cannot extrude in or out.

From these steps, I've ruled out any hardware issue with the stepper, motor, RAMPS 1.4.
From what I can tell, this issue seems to be either the Firmware or the Software.
Any one got any ideas?