Set up Microsoft Authenticator App for Office 365

Go to: https://aka.ms/MFASetup
Click on "+ Add Method"
Select "Authenticator app" and click "Add"
- You can download the Microsoft Authenticator App from the appropriate App Store
Click next until you see the QR Code
In the app on your phone, add Work Account and scan the QR Code
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On the Security Info page, you can change the "Default sign-in method:" by clicking on the "Change" link and selecting "Microsoft Authenticator"