Set up multifactor authentication on your Microsoft 365 account

Your password is one lock. Multifactor authentication adds a second one, so that someone who has stolen or guessed your password still cannot reach your account without your phone in their hand. You set it up once, and after that you approve a prompt occasionally.

Before you start

Have your phone with you and connected to wifi or mobile data. You will install an app on the phone and scan a code from your computer screen, so you need both in front of you at the same time.

If we manage your phone, Microsoft Authenticator may already be installed. Check before you download it again.

Step by step

1. Start the setup. Sign in to Microsoft 365 on your computer as you normally would. If we have already switched multifactor authentication on for you, a box appears headed Help us protect your account. Click Next. If you are setting this up ahead of time, go to aka.ms/mysecurityinfo instead, sign in, and choose Add sign-in method.
2. Install Microsoft Authenticator on your phone. Click Download now on your computer, or search for Microsoft Authenticator in the App Store or Google Play. It is free and published by Microsoft Corporation. Install it, open it, accept the prompts, but do not add an account yet. Go back to your computer and click Next.
3. Confirm it is you. Microsoft will not trust a new app without checking who you are first. Choose the phone option and enter your mobile number. A code arrives by text. Type it in and click Next.
4. Scan the code. Your computer shows a QR code, the square black and white pattern. On your phone, open Authenticator, add an account, choose Work or school account, then Scan QR code. Point the phone at your screen. If the phone asks for camera permission, allow it, because without the camera it cannot read the code.
5. Approve the test. Your computer sends a test notification. Open it on the phone and tap Approve. Click Done on the computer. That is it.

What changes from now on

Most of the time you sign in with your password as usual. Every so often, and always on a device you have not used before, your screen shows a two digit number and your phone gets a notification. You open the notification and type in the number from the screen.

That number matters. It stops you approving a sign in by accident, and it stops an attacker who already has your password getting in by sending you prompt after prompt until you tap approve out of irritation.

When it does not go smoothly

The notification never arrives.

Open Microsoft Authenticator yourself instead of waiting. It shows a six digit code that changes every thirty seconds. Type that into the sign in screen.

You have a new phone.

Install Authenticator on the new handset and add the account again at aka.ms/mysecurityinfo before you get rid of the old one. If the old phone has already gone, call us and we will reset your methods.

You are abroad with no signal.

The six digit code in the app is generated on the phone itself, so it works with no connection at all. Use that.

You would rather not put a work app on your personal phone.

Tell us. There are other methods, including a physical key, and we would rather find one that suits you than have you working around the security.

If you get stuck

Call the service desk on 03333 22 11 00 or email support@easylifeit.com. Say you are setting up multifactor authentication and roughly where you got to, and we will take it from there.

Setup sequence checked against Microsoft’s own documentation, Set up multi-factor authentication for Microsoft 365, September 2026. Microsoft changes these screens from time to time. If what you see does not match what is written here, call us rather than guessing.