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    How to Set Up the Microsoft Authenticator App

    6 min read
    Updated 20 February 2026

    What is the Microsoft Authenticator App?

    Microsoft Authenticator is a free app that adds a second layer of security to your Microsoft 365 account and other services. Instead of just using a password, you also confirm your identity on your phone — making it far harder for anyone to access your accounts even if they know your password.

    This guide walks you through setting up the app on your phone and linking it to your Microsoft 365 account.

    Before You Start

    You will need:

    • Your iPhone or Android phone
    • Access to the Microsoft 365 account you want to secure
    • A computer or tablet to complete the setup steps

    Step 1: Download the Microsoft Authenticator App

    On iPhone:

    • Open the App Store
    • Search for Microsoft Authenticator
    • Tap Get to download it (it is free)
    • Open the app once it installs
    On Android:
    • Open the Google Play Store
    • Search for Microsoft Authenticator
    • Tap Install
    • Open the app once it installs
    Make sure you download the official app published by Microsoft Corporation — look for the blue shield icon.

    Step 2: Open Your Microsoft 365 Security Settings

    On your computer or tablet:

    • Go to mysignins.microsoft.com and sign in with your Microsoft 365 work account
    • Click Security info in the left-hand menu
    • Click + Add sign-in method
    • In the dropdown, select Authenticator app
    • Click Add
    Microsoft will now guide you through linking the app to your account.

    Step 3: Link the App to Your Account

    Microsoft will display a QR code on your computer screen.

    On your phone:

    • Open the Microsoft Authenticator app
    • Tap the + icon in the top right corner
    • Select Work or school account
    • Tap Scan a QR code
    • Point your phone camera at the QR code on your computer screen
    • The account will be added automatically

    Step 4: Test the Connection

    Microsoft will ask you to approve a test notification to confirm everything is working:

    • A notification will appear on your phone
    • Tap Approve
    • If successful, you will see a confirmation on your computer
    Your Microsoft Authenticator is now set up and linked to your account.

    Step 5: Set Authenticator as Your Default Sign-In Method

    To make sign-in smoother:

    • Back on the Security info page, find the Authenticator app entry
    • Click Set as default
    • From now on, when you sign in to Microsoft 365, you will get a push notification on your phone to approve

    How Sign-In Works Day to Day

    Once set up, signing into Microsoft 365 works like this:

    • Enter your email address and password as normal
    • A notification appears on your phone
    • Open the notification and tap Approve
    • You are signed in
    The whole process takes a few seconds. You can also open the Authenticator app and use the 6-digit code that refreshes every 30 seconds if you prefer.

    What If I Get a Sign-In Notification I Did Not Request?

    This is a red flag. If you receive an Authenticator approval request when you are not signing in:

    • Tap Deny immediately
    • Contact your IT team — someone may be trying to access your account
    • Change your password as soon as possible
    Never approve a notification you were not expecting.

    What If I Lose My Phone or Get a New One?

    If you lose your phone:

    • Contact your IT team immediately
    • They can remove the Authenticator from your account
    • Once you have a new phone, set it up again using the same steps above
    It is a good idea to set up a backup sign-in method (such as an alternative phone number) so you are not completely locked out if something goes wrong.

    Troubleshooting

    The QR code did not scan:

    • Make sure your camera lens is clean
    • Try increasing the brightness on your computer screen
    • Move the phone slightly further back from the screen
    The notification is not arriving:
    • Check that your phone has a mobile or WiFi connection
    • Make sure notifications are enabled for Microsoft Authenticator in your phone settings
    • Try using the 6-digit code from the app instead
    The app is asking for camera permission:
    • Go to your phone settings and allow the Authenticator app to access the camera

    Need Help?

    If you are having trouble setting up the app, contact Netluma IT and we will walk you through it.

    Phone: 1300 521 162 Email: helpdesk@netlumait.com.au

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