OverviewZTE N9511Source

Switch off the device. Hold down the Volume Up key and the Power button. When the "Boot Mode" appears, release the keys and open the "Recovery Mode" using the Volume keys. Now hold down...

Switch off the phone, then hold down the Volume Down key and the Power button. Next, choose "Clear eMMC" using the Volume keys and the Power button. All done! Wait until your device restarts.

Switch on the device and go to "Settings". Next, choose "Backup & Reset". Here click on "Factory data reset". Select "Reset Phone" and "Erase everything"...

Switch on the device and go to "Settings". In Settings go for "Language and input". Next, choose "Language". That's all! The language has been changed!

The phone must be on. Use Dialer to enter the proposed code: *983*22387#. Finally, choose "Yes". Great! Wait until the process is completed.