How to Unlock a T-Mobile MDA
- 1). Turn off the T-Mobile MDA. Slide the battery release button to open. Slide the back cover off the MDA. Remove the battery from its compartment. Remove the T-Mobile SIM card from this compartment.
- 2). Insert the SIM card from your new company into the slot with the gold contacts facing down and the cutaway corner facing away from the slot. Replace the battery and snap the battery cover back into place.
- 3). Turn the MDA back on. Click "OK" at the SIM card error display. Input the SIM unlock code in the field provided. Click "OK" to unlock the phone.
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