MFA not working in Outlook 2016

Hello all


I have an Office 365 business account (Office 365 Business Premium). I am using MFA (text message to phone) for that account, which is generally working fine when I am using Word 2016, Excel 2016, etc.


But when I try to configure this Office 365 account in Outlook 2016 (version 16.0.8528.2147) on Windows 10 Pro (version 10.0.16299.0) it's not working.


Adding Office 365 Account to Outlook 2016


Step 1: I enter the e-mail adress of the account to be added (e.g. *** Die E-Mail-Adresse wurde aus Datenschutzgründen entfernt. ***):





Step 2: Account is being added:





Step 3: After a while I am get a Windows prompt for providing the username and password. I expect to get the MFA window (see below the screenshots of Windows Mail, steps 3-5) instead of the Windows username and password prompt. As username I inserted the email address in format like *** Die E-Mail-Adresse wurde aus Datenschutzgründen entfernt. *** and password (which is correct).




Step 4: After a while I get the following window with an error message





If I do the same steps with Windows Mail (on Windows 10 / version 10.0.16299.0 / same computer as above with Outlook 2016), it works.


Adding Office 365 Account to Windows Mail


Step 1: I enter the e-mail adress of the account to be added (e.g. *** Die E-Mail-Adresse wurde aus Datenschutzgründen entfernt. ***):





Step 2: I have to enter the password:





Step 3: The following dialog "Help us to protect your account", Your Administrator requires additional security:





Step 4: For the additional security authentication I choose "text message to phone" and insert my country and phone number:





Step 5: I insert the received code:





Step 6: The account is successfully added and working:





What we already checked

• DNS configuration in the admin center under portal.office.com.
  
• The Remote Connectivity Analyzer, test "Outlook Auto Discover", which works fine.

Additional Information

• If we disable the MFA in admin center, the account can be easily configured in Outlook 2016 and Windows Mail.
• The computer is joined to the AzureAD
  

Any ideas, which the Office 365 Account is not working in Outlook 2016 with activated MFA?

If you need further information, just ask me.


Many thanks


Yannick