Using the hardware keys to remove password or reset the gesture lock
1. Turn off the phone completely.
2. Press and hold both Volume UP (and HOME) + power on the phone.
3. When Android Recovery menu screen appears release all keys.
4. Navigate and highlight “wipe data / factory reset” using the Volume down key
And press power.
5. Navigate and highlight again to yes — delete all data and press power.
6. All data will be lost! Before doing a hard reset backup all important data.
After hard reset is done select Reboot system now. Press power to reboot the phone.
Another way to reset your Z1 is to enter the reset code on dial screen.
On dial screen enter this Samsung Z1 reset code: *2767*3855#
All data will be lost!
Use Samsung Galaxy Z1 Backup and reset function
Go to Settings > Backup and reset > Factory data reset: Reset settings to the factory default values and delete all data.
Your device freezes or has fatal errors
If your device freezes or hangs, you may need to close applications or reinsert the battery and
Turn on the device to regain functionality. If your device is frozen and unresponsive, press and
Hold the Power button for more than 8-10 seconds to reboot.
If this does not solve the problem, perform a factory data reset. On the Applications
Screen, tap Settings -> Backup and reset -> Factory data reset -> Reset device -> Erase everything. Before performing the factory data reset, remember to make back-up copies of all important data stored on the device.