Before you buy a new cell phone or new tablet, please try the following procedure to repair your device. First charge your battery, backup your important data if possible and in most cases take out SIM and SD card before factory reset. It is impossible to recover your data after doing a hard reset, so online backup is always important. For all of your data, a backup should be done on an external device, hard drive, raid system or media. With or without insurance, if your cell phone lost, damaged or stolen at least your invaluable data is backed up in a safe place. If you are about to sell your phone and you want to wipe your personal data, or if your phone affected with virus you have to do a hard reset. In some cases, you can delete the forgotten password or lock pattern from your device as well. All information is for devices with stock based ROMs. If you are using rooted device, always back up your EFS folder first, containing your IMEI info, etc.!

    Samsung Galaxy Ace Duos S6802 hard reset

    Reset you Samsung Galaxy Ace Duos S6802 Your device freezes or has fatal errors

    If your device freezes or hangs, you may need to close programs or reset the device to regain functionality. If your
    device is frozen and unresponsive, press and hold the Power key for 8-10 seconds. The device will reboot automatically.
    If this does not solve the problem, perform a factory data reset. In Idle mode, open the application list and select
    Settings → Privacy → Factory data reset → Reset phone → Erase everything.
    Andorid 4.0 or newer ICS
    Select Settings → Back up and reset→ Factory data reset → Reset device→ Delete all.

    Select Settings > Privacy > Factory data reset: Reset your settings to the factory default values and delete all your data.

    Press Application button, then Settings > Reset settings: Reset your settings to the factory default values.

    While using your device, be sure to back up important data. When disposing of your device, back up all data and then reset your device
    to prevent misuse of your personal information.

    Use this method to hard reset your Samsung Galaxy Ace Duos S6802: Enter *2767*3855#. Warning! All your data including contacts, messages etc. will be lost! Copy all your necessary data/Contacts/Messages etc. to SIM or make backup to your PC before full reset! Take out SIM card before full reset.