Once your Account enabled MFA/2FA, first-time sign-in required to add information for account secure

Step1: Sign-in Webmail (https://portal.office.com)

Click Next


Step 2: Enter your Phone Number for verification

the select method is "Send me a code by text message" and click Next


Step 3: Verify your phone number with SMS code

you will receive SMS with 6-digit number for verification


Step 4. Your App Password

This is app password for some applications may not verify by SMS, so you need to use this password for sign-in. (e.g. Thunderbird Pop3/Imap, Rainlendar and Old Version Outlook 2013 and 2010)

You can Ignore it without record this password, later you can create a new one, but you can't retrieve this password.

If you are using Outlook 2013 or 2010, please record this password, your outlook will pop-up and you required this password for access email.

Click Done


 

MFA / 2FA was done!

  1. First time when you open Outlook and Webmail you need MFA to verify by SMS
  2. Your Mobile may popup 3-4 times for SMS verify because you need to verify all the Office 365 login such as Outlook, Microsoft Teams, Onedrive, and Sharepoint. When it automatically popup ask few times for MFA SMS, you can't identify which SMS verification code for which apps. So you may need to sign out and sign in to verify the app's individual.
  3. Some application may popup request new password, but that the application does not support MFA, that means you will receive SMS verification code, but your apps is no area to enter the verification code, then you will reject by login processing, so you need to refer the Step4. and using Additional Apps Password for sign-in.

 

Additional Link
User Profile
https://account.activedirectory.windowsazure.com/r/#/profile

Change Password
https://account.activedirectory.windowsazure.com/ChangePassword.aspx

Additional security verification
https://account.activedirectory.windowsazure.com/Proofup.aspx

App Passwords
https://account.activedirectory.windowsazure.com/AppPasswords.aspx