If your organization is using multi-factor authentication (MFA) for Microsoft 365, the easiest verification method to use is the Microsoft Authenticator smart phone app. It's just one click instead of typing in a 6-digit code. And if you travel, you won't incur roaming fees when you use it.
Download and install Microsoft Authenticator app
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Download and install the Microsoft Authenticator app for Android, iOS or Windows Phone.
Set up the Microsoft Authenticator app
Choose the mobile app
Open a browser on your computer and go to portal.office.com. Sign in to your Office 365 for business account.
Use these steps if you see this screen:
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Click Set it up now.
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Choose Mobile app from the dropdown.
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Make sure "Receive notifications for verifications" is selected. Click Set up.
Use these steps if you see this screen:
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Click here.
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In the drop down box under What's your preferred option, choose Notify me through app.
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Check the box for Authenticator app or Token, and then click Set up Authenticator app.
Wait for configuration pop-up box.
You should see a window on your computer that looks like this.
Add account to Microsoft Authenticator
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Open the Microsoft Authenticator app on your phone.
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Tap the + > Work or school account.
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Use your phone to scan the QR square that is on your computer screen.
Notes:
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iPhone users may have to enable the camera in Settings in order to scan.
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If you can't use your phone camera, you'll have to manually enter the 9 digit code and the URL.
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Your account will be added automatically to the app and will display a six-digit code.
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Confirm activation status on your computer
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Switch back to your computer and click Done.
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Now wait for the Checking activation status text to finish configuring your phone.
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When it's complete, you'll be able to click the Contact me button on the right.
Note: If configuration fails, just delete retry the previous steps again.
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Approve sign in on your phone
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Switch back to your phone and you'll see a notification for a new sign in.
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Go to the Microsoft Authenticator app.
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Tap Approve to allow it.
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Finish set up
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Back on the computer, follow any prompts that you might see such as adding a mobile number.
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You're good to go!
From now on, whenever you have a new sign in or add your Microsoft 365 work or school account to an app, you'll open the Authenticator app on your phone and tap Approve.