
Adding multi-factor authentication to your log in procedure can help prevent breaches from occurring. While any method will add another layer of protection, using an authenticator application can in many ways be more secure than an SMS text message code. While you can use any authentication app for your Office 365 account, this guide uses Microsoft Authenticator for its instructions and corresponding pictures.
Prerequisite: Enable MFA
If this is a work or school account, your administrator will have to enable multi-factor authentication in the admin portal.
Then we recommend following the basic set up, to prepare your mobile phone as your security device. You can find those instructions in our article, Multi-factor authentication for Office365 user setup.
Access your security settings
Start by opening the browser of your choice and going to Office.com. Once you are logged in, you can access security settings by clicking the icon in the upper right of your window. Then click view account.

Next, click security info in the left-hand menu, or the update info link under the Security info section on the main account page.

Add a security factor
The Security Info section will show the methods you have set up for sign in or account reset. Click the plus add method option at the top.

Select Authenticator app, and then click add.

You will be prompted to download the Microsoft Authenticator app. This dialogue includes a link to the app or you can find it in the app store for iPhone or the Google Play store for Android. Click the next button to begin.

Setting up Microsoft Authenticator on your smart phone
After you have downloaded and installed Microsoft Authenticator on your smart device, it’s time to link it to your Office 365 account.
In the app, tap the vertical dot dot dot in the upper right corner of your phone screen. Then tap Add account.

When prompted, select school or work account. (If this is not a business account, select personal. The following steps are very similar.) Log into your account with your username and password.

This will open a barcode scanner on your phone. If prompted, please allow the application to access your phone’s camera.
Take your phone and scan the QR code that is displayed on your computer screen. You will not need to click anything for it to scan.

Once your phone says “account set up successfully” and you see the account in the authenticator app, click next on your computer. Microsoft will send a test approval request to your phone. Click approve on your phone.

Your account is now secured with multi-factor authentication, using the Microsoft Authenticator app.
Logging in after setting up MFA for O365
The next time you login to your account from a new computer, you will have to enter your username and password as normal, but you will also have to press approve on your phone to get access. If you ever see the approval request pop up on your phone when you are not signing in, click deny. Then either open a ticket with your IT provider and/or reset your password.
From there, feel free to use this Authenticator app to set up MFA for more accounts than just your Microsoft Account. It’s important to secure all your accounts including social media accounts such as Facebook, Instagram, and Twitter, or other email accounts.
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