Factory resetting wipes all your stuff from your A5, which can be useful if you're selling it or trading it in. It will also help you get back into your phone if you're locked out.
You need to back up your phone before you reset it so you don't lose your stuff (messages, pictures and videos and so on). If you've got a Google account on it, things like settings and contacts will probably already be safe. Check in Settings > Accounts > Google to see if the account's there, and what's being backed up or 'synced' online.
To save your pictures, videos and music, you'll need to back your phone up to your computer. Download Samsung's Smart Switch software and follow the instructions in our guide to backing up your smartphone to your computer.
If the phone doesn't do anything when you touch the screen or press a button, it might have just crashed.
Press and hold the Power and Volume down buttons together for at least 7 seconds to restart the phone. Hopefully it'll come back on as normal, and ready to use.
If you just want to wipe it to sell or trade it in, reset the phone through the Settings menu by following these steps.
Tap Apps > Settings > Backup and reset.
Tap Factory data reset.
Tap Reset device.
Tap Erase everything.
When the phone comes back on, you'll see the 'Setup Wizard', just like it's a new phone. If you're not using it again, press the power button for a few seconds to turn the A5 off.
You can wipe your phone and reinstall the operating system using a computer. You'll need a computer with internet access and Samsung's Smart Switch software installed, and a USB cable to connect your phone.
Open Smart Switch on the computer, then connect the phone.
When you see your phone appear, click More.
On the menu bar at the top, click Tools.
Click Emergency Software Recovery and Initialisation.
You'll see a pop-up window showing the new software version, and a warning that you'll lose all your stuff. Click OK to carry on.
When the software has been downloaded and installed, close Smart Switch and unplug your phone.
If all went well, the phone will show the 'Setup Wizard' ready for you to use it again, or turn it off if you're getting rid of it.
Use the built-in Android Recovery option to reset your phone if you can't get into it, or can't open the Settings menu. You'll need to enter your Google account details again when you set the phone up afterwards.
Hold in the Home and Volume up buttons.
Now press and hold the Power button at the same time. Keep them all pressed for 5-10 seconds.
You'll now see the Recovery menu. It can be a bit tricky to hold all the buttons at the same time, so if the phone starts normally, you should repeat the steps.
Use the Volume buttons to highlight wipe data/factory reset, then press the Power button.
Highlight Yes - delete all user data and press the Power button to reset your phone.
When the reset finishes, reboot system now will be highlighted. Press the Power button to restart the phone.
When the phone restarts, it'll be wiped and ready for you to go through the Setup Wizard. If you're not going to use the phone again, turn it off with the Power button.
If your phone's missing, find it or wipe it remotely with Android Device Manager (ADM). You'll need to log in with the Google account that's on your phone, and it'll only work if your phone's still turned on and connected to the internet.
Go to the Android Device Manager website.
Log in with your Google account.
If your phone's still turned on, you'll see its location on a map. If that's where you are, click Ring to play the ringtone at full volume, even if the phone's on silent.
To wipe it, click Erase.
Confirm you want to wipe the device by clicking Erase again.
Even if it isn't on right now, ADM will still send the command, and as soon as your phone reconnects to the internet it'll reset itself.
That's everything you need to know to reset your Samsung Galaxy A5, but if you need more help, you can get in touch with a Team Knowhow Expert here.
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