How to Unlock a T-Mobile Sidekick 3 With a SIM Card
- 1). Power down your Sidekick 3 and remove the old SIM card.
- 2). Insert your non-accepted SIM card provided to you by your new network provider and power on your device.
- 3). Enter your unlock code when prompted by the title on the screen "Special Code Required." The unlock code can be 1 to 8 digits long. Once you have entered the code press "Enable."
- 4). Wait for the message to finish reading "Authenticating code." After it has finished authenticating your unlock code, your T-Mobile Sidekick 3 is unlocked.
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