These are the steps and procedures on how to hard reset the T-Mobile T839 Sidekick 4G with Android OS, v2.2 (Froyo), 1 GHz ARM Cortex-A8 processor, PowerVR SGX540, GPU, Hummingbird chipset.
This is a simple guide if you want to return the device to its original factory settings again.
T-Mobile Sidekick 4G Factory data reset:
1. On the main home screen, select menu
2. Select Settings, then Privacy
3. Select Factory data reset
4. Select Reset phone
5. Enter the password if prompted, then confirm by selecting Erase everything
T-Mobile Sidekick 4G Hard reset, this may help if the phone experience some hang or frozen on some applications:
1. Turn the phone's power off. Take the battery out from the device, wait a couple of seconds and reinsert it back again.
2. Now, Hold the Volume Down button
3. Then press and hold the Power button until the device turns on
4. A menu will show up like: Fastbook, Recovery, Clear Storage, and Simlock
5. Just select Clear Storage by pressing the Volume Down button
6. Then press and release the Power button
7. Select Volume Up if YES and Volume Down for NO
Once the reset process is complete, the phone will then reboot to its factory fresh state settings.
Any data including third-party applications previously stored from the HTC Sensation already wiped or deleted.