Uno + SainSmart Motor Shield Servo works DC and Stepper don't

Not sure what the deal is. When I plug in a servo and run servo sweep example it works fine. When I hook up DC or stepper motor and run the corresponding Adafruit dc motor or stepper motor test in the Adafruit Motor Shield V2 Library, neither one works.

I am powering the motor shield with 4 AA batteries. The DC motor is a little Radio Shack Micro Super High Speed motor. 6VDC 100mA max. If I just take the two leads and touch them to the power terminals on the motor shield the motor runs fine. When I hook things up as instructed in the Adafruit tutorial I get nothing.

Now being new to this but having a little common sense I thought why not use my multimeter and see if the voltage is switching on and off so I would know if the motor was even getting power and I got nothing.

Any guidance you can provide would be appreciated.

Thank you!