To perform Hard Reset on this Xperia E, you just need to make sure that all the data has already been backuped
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Reset Via Settings
Select Apps from yourHome screen
Tap Settings
Tap Backup & reset.
Tap Factory data reset
Tap Reset phone.
Tap Erase everything.
To avoid permanent damage to your device, do not restart your device while a reset procedure is underway.
Warning! All data will be erased from device memory, including system and application data, settings and downloaded applications. Back up your important data. The device will restore to factory settings.
Performing Soft Reset
If your phone hangs or does not responding, try to Press and hold power key about 10 seconds. It will rebooting automatically. Or try to remove and re insert the battery and SIM Card.