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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.