MFA: Setting up the Microsoft Authenticator App using Mobile Phone/Device only
Summary
This article explains how to set up the FREE Microsoft Authenticator app for multi-factor authentication (MFA) for M365 using only your mobile phone or mobile device. Use these instructions if you want to add the Authenticator mobile app but do not have access to a computer.
Warning: Be sure you select the "Microsoft Authenticator" app provided by the Microsoft Corporation for FREE. Several other apps with similar names have similar icons but are not the trusted, free Microsoft app.
Icon for the Microsoft Authenticator app provided by the Microsoft Corporation. This is a FREE app - do not pay for an app for this purpose.
How-To
Task: To add the FREE Microsoft Authenticator app as an MFA method using only a mobile phone or mobile device.
Instructions
Step 1 - In a web browser, go to: myaccount.microsoft.com and sign in if prompted.
Step 2 - Tap on UPDATE INFO in the Security info tile.
Step 3 - On the Security info page, tap on Add sign-in method
Step 4 - In the Add a method box, tap on the Choose a method menu.
Step 5 - From the Pop-out menu choose Authenticator app
Step 6 - In the Add a method box, tap on Add
Step 7 - Tap on Download now if the Microsoft Authenticator application is not already installed. Follow the steps to install the app. Otherwise, if the app is already installed, skip to step 8.
Step 8 - Return to the browser page shown in step 7. Tap Next.
Step 9 - Tap on Pair your account to the app by clicking this link, then tap Open if prompted.
Step 10 - Tap Next. This should prompt for approval of a push notification
Step 11 - Once approved, a screen will appear showing the notification was approved. Tap Next to return to the Security info page. You're all set and can now use the Microsoft Authenticator app for Multi-Factor Authentication (MFA).
Outcome
Users who have set up Multi factor Authentication for M365 will be prompted to MFA periodically when signing into Email, Teams, OneDrive sync, and other M365 tools on both their computers and their mobile devices. For other applications in the Single Sign-On (SSO) environment,users may be prompted to MFA when logging into those applications as well.