Samsung Trend hard reset

Use this method to hard reset your Samsung Trend GT-S7392 phone: 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.
Resetting Your Phone
Press and hold for 8-10 seconds to reset the device if it has fatal errors or hang-ups, or freezes.

Your device freezes or has fatal errors
If your device freezes or hangs, you may need to close applications or reinsert the battery and
turn on the device to regain functionality. If your device is frozen and unresponsive, press and
hold the Power button for 8-10 seconds to reboot.
If this does not solve the problem, perform a factory data reset. On the Applications screen, tap Settings → Backup and reset → Factory data reset → Reset device → Erase
everything. Before performing the factory data reset, remember to make back-up copies of all important data stored on the device