M365 MFA with Outlook Mobile Approval

Outlook Mobile can approve your Microsoft 365 sign-ins with a simple tap. This is the easiest MFA method — no codes to type, just approve the notification on your phone.

Prerequisites

• An iPhone or Android phone
• The Outlook mobile app installed (iOS App Store | Google Play Store)
• Your M365 account already added to Outlook mobile

Note

If you haven’t set up Outlook on your phone yet, do that first. Sign in with your M365 email and password. MFA setup will be much smoother once Outlook is already working.

Setting Up Outlook Mobile Approval

1. On your computer, go to https://aka.ms/mysecurityinfo and sign in with your Microsoft 365 account.

2. Click + Add sign-in method.

3. From the dropdown, select Authenticator app and click Add.

4. Microsoft will show setup instructions. Click Next to continue.

5. On the “Set up your account” screen, select I want to use a different authenticator app (if prompted) or proceed to the next step.

6. When shown the QR code screen, look for the option “I can’t scan the QR code” or “Having trouble?” and click it.

7. Select Use a verification code from my mobile app or similar option that mentions using an existing app.

8. Microsoft will display a 6-digit code and instructions. On your phone, open the Outlook app.

9. In Outlook mobile, you should see a prompt to approve the sign-in. If not, check your notifications.

10. Tap Approve on your phone. The number shown should match what’s displayed on your computer.

11. Back on your computer, click Next to verify the setup worked.

12. Microsoft will confirm your authenticator is configured. Click Done.

Using Outlook Mobile Approval

Once configured, signing into M365 works like this:

1. Enter your email and password as normal on the sign-in page.

2. Microsoft will send a push notification to Outlook on your phone.

3. Open the notification or Outlook app. You’ll see a prompt showing:

   • The app/service requesting access
   • A two-digit number to verify

4. Confirm the number matches what’s shown on your computer screen.

5. Tap Approve to complete sign-in.

Tip

If you don’t receive the notification, open Outlook manually — sometimes notifications get delayed. You can also check your phone’s notification settings to ensure Outlook can send alerts.

Troubleshooting

Not receiving approval requests?

• Ensure Outlook has notification permissions on your phone
• Check that you’re signed into the correct M365 account in Outlook
• Try force-closing and reopening Outlook

Number doesn’t match?

• Do not approve — this could be someone else trying to access your account
• Deny the request and change your password immediately

Want to switch to a different MFA method?

• Visit https://aka.ms/mysecurityinfo to manage your sign-in methods