Unlock your ZTE Grand Memo V9815

OS: Android 4.1.2 (Jelly Bean)

CPU: Quad-core 1.7 GHz Krait 400

Display: 5.7" inc

Camera: 13 MP, Single

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 phone to PC with USB cable and open Tenorshare 4uKey for Android.
Press the Remove button in the menu that appears on the PC screen.
The program will warn you about deleting all data from the smartphone, to continue working, click OK.
Wait until the operation is completed, and then put your smartphone into recovery mode according to the prompts on the computer screen.
Click the Next button, then follow the steps recommended by the program to restore the device to factory settings and reboot it. After rebooting the smartphone, the screen lock will be disabled.

2. Make a hard reset (factory reset)

To get started, turn off your phone.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.
Select Wipe data/factory reset. using volume buttons to navigate through the menu and confirm selection by pressing the power button.
Confirm hard reset.

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

You need to ensure that the phone battery is discharged. 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 go to the security menu and disable the lock.

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

You need to turn off the phone and remove the tray with the memory card.
Transfer the Aroma File Manager program using a computer to the phone's memory card. Insert the memory card back into the phone.
Using a combination of buttons, put your smartphone into recovery mode.
In recovery mode, select Install zip -> Install zip from sdcard -> Choose zip from sdcard, go to the archive folder with this program and select it.
After starting the program, you will need to go to the folder /data/system 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)
Restart your smartphone. The screen lock will be released.

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

After several unsuccessful ways to unlock the phone, Forgot password? will appear on the screen. Click on it.
Choose to restore access with your Google Account. You will need to enter your Google Account username and password.
Remove the screen lock from the 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.