Unlock your ZTE Nubia Z9 Classic

OS: Android v5.0.2 (Lollipop)

CPU: 1.5 GHz, Octa Core Processor

RAM: 3 GB

Display: 5.2 inches, 1080 x 1920 pixels

Battery: 2900 mAh, Li-ion Battery

1. Use the Tenorshare 4uKey for Android app.
2. Make a hard reset (factory reset).
3. How to use a low battery to unlock a phone locked with a graphic key.
4. Delete 'gesture.key' and 'password.key' using Aroma File Manager.
5. Restore access to your smartphone using your Google Account.

1. Use the Tenorshare 4uKey for Android app.

Connect your smartphone to your PC and launch the 4uKey for Android program.
Press the Remove button in the menu that appears on the PC screen.
The program will warn you about deleting all data on the phone, to continue working, click OK.
Wait until the end of the operation, and put your smartphone into recovery mode according to the prompts on the computer screen.
Click the Next button and follow the instructions on the screen. After starting the smartphone, the screen lock will be disabled.

2. Make a hard reset (factory reset)

Turn off your smartphone.Simultaneously press and hold for about 10-15 seconds one of the button combinations:
Volume down button + Power button;
Volume up button + Power button;
Volume down button + Power button + Home button;
Volume down button + Volume up button + Power button.
Select Recovery using volume up/down buttons to navigate through the menu and confirm selection by pressing the power button.
Using the volume buttons to navigate through the menu, select Wipe data/factory reset. and confirm by pressing the power button.
Finally confirm the hard reset operation.

3. How to use a low battery to unlock a phone locked with a graphic key.

You need to discharge the battery. To speed up the process, make sure that the screen is constantly lit.
When the battery has a few percent left, the phone will report this and open the menu with power settings, that is, it will unlock the phone.
You need to quickly find the page with security settings in the menu and disable the lock.

4. Delete 'gesture.key' and 'password.key' using Aroma File Manager.

Turn off your smartphone and remove the memory card from it.
Transfer the Aroma File Manager program using a computer to the phone's memory card. Insert the memory card back into the phone.
Put your smartphone into recovery mode using the appropriate button combination for your model.
In recovery mode, select the Install zip option. Then select Install zip from sdcard, Choose zip from sdcard, go to the archive folder with this program and select it.
You need to find the /data/system folder and delete the files 'gesture.key' and 'password.key' (for Android 4.4 or lower) or 'getekeeper.password.key' and 'getekeeper.pattern.key' (for Android 5 or higher)
Reboot your phone. The block will be removed.

5. Restore access to your smartphone using your Google Account.

After several attempts to unlock the phone, Forgot password? will appear on the screen. Click on it.
You will be asked to enter your Google Account username and password.
Delete in the lock screen settings.

Thomas Nilan
Smartphone Expert

Thomas Nilan is a mobile phone expert with in-depth knowledge of the Android and iOS operating systems, who understands the settings of various hidden features that allow you to expand the capabilities of your smartphone, as well as get information about what is going on inside the phone for future repairs. He is an authority in his field, which has allowed him to become a ghostwriter for several technology publications, and he enjoys writing small mobile applications for testing smartphones.