How to factory reset Samsung mobile devices
Samsung mobile phone running Android OS can be easily formatted and returned to factory status manually even in the case that the phone can not be started.
In the case that your phone is working properly you can do a factory reset by heading to settings >> backup and reset >> Factory Data Reset then follow the instructions to reset your phone.
Alternatively you can do a factory reset by long pressing Power + Home + Volume Up keys until you enter the Android recovery menu where you can choose the option Wipe data / factory reset to manually resetting your device to the factory status.
You must be aware that the touch screen will not function in the recovery menu and you have to use the Volume Up or Down keys to choose your desired option, also you select the option by pressing the power key.