When you do a factory reset, all your data and information will be deleted. You need to back it up if you want to get it back after the reset. We've got a guide dedicated to backing up your phone here.
If your phone is working, you can use the settings to do the reset. Here's how.
Open the Settings and go to About.
At the bottom of the page, tap Reset Phone, then confirm it by choosing Yes.
You'll have to choose Yes again, and then the phone will start the reset.
When the bar has finished moving across the screen, the Lumia 635 will restart, ready to be set up again.
You'll need to do the reset this way if you can't get into your phone. It's a combination of buttons that need to be pressed exactly, so read through the steps and then have a go.
Start by turning the phone off.
Press and hold the Power and Volume down buttons together.
When you feel the phone vibrate, let go of the Power button but keep holding the Volume down button.
Keep hold of the Volume down button until you see an exclamation mark on the screen, then you can let it go.
If you make a mistake and the phone starts to turn on, take the battery out for about 10 seconds and then start again.
With the exclamation mark on the screen, press these buttons in this order:
You will feel a small a vibration when you press the last button, and the Microsoft logo will pop-up followed by some spinning cog wheels. A loading bar will pop-up and start moving across the screen. When it's done, the phone will turn on and will need setting up again.
If you've lost your phone and need to wipe it, remotely wiping the phone is the next best option to make sure your personal data is totally gone.
To remotely wipe your Lumia 635, you'll need to know your Microsoft account's email address and password, and have access to a computer or other web-connected device.
Go to My Devices on a computer and log in with your Microsoft email address and password.
The phones connected to the account will be shown. Find the Lumia 635 and click Find my phone next to it.
When the information page comes up, click Erase.
Tick the box to say that you want to wipe the phone, then click Erase again.
The instruction will be sent, and the next time your phone gets an internet connection, it'll erase itself.
If none of the ways above seem to work, you can try resetting it with your computer. Here's how.
Download and install the 'Windows phone recovery tool' here.
Open it, and then connect the Lumia 635 to the computer with a USB cable.
Click the Lumia 635 and you'll be shown the Operating System that's available. Click Install software.
Click Confirm to start, and the software will be installed on the phone.
When it's finished, the Microsoft logo will pop-up on the screen and you'll be able to set it back up.
Hopefully that's you sorted, but if you need more help, you can get in touch with a Team Knowhow Expert here.
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