This process is recommended for your device if : it is frozen, it doesn’t turn on or you are experiencing a software issue. It will allow you to perform a low level format on your device. Thus all the data will be deleted, you won't be able to retrieve them.

1. We strongly recommend to back them up first.
2. Keep in mind that your device’s battery must be charged enough to perform this operation.

1. If you can have access to the Windows Phone® interface
   
   1. Press the ON/OFF button to turn on your device
   2. On the device's homescreen, pull down the status bar and select All settings
   3. In the System section, scroll up the menus then select about > reset your phone
2. If you can’t access the Windows Phone® interface
   
   1. Turn off the mobile phone (you can also remove the battery and replace it to turn off the phone)
   2. Hold Volume - then plug your phone to the power connector until a question mark is displayed
   3. Press once the following buttons one after the other : Volume +, Volume -, ON/OFF, Volume -
   4. The mobile reboots and a notched wheel displaying the running process appears. After a certain period of time, your mobile phone will reboot. At the end of the resetting process, your mobile phone will ask you to do the setup through a wizard

If the question mark is not displayed or you missed a step, restart the whole process.