Ever tried setting up Outlook with Office 365 for an account with MFA? Then most likely you forgot to add an App-password and instead provided your regular password. Office 2016 and older, still do not have support for MFA accounts and SSO is not applicable.
Are you an Office 365 admin? Want to remove the need for this for all your users and increase your baseline security? Read here and enable "Modern Authentication" which for one allows for direct MFA support.
So once you've realized your mistake, you are stuck... And Office 365/Outlook doesn't ask you for the password anymore. So what do you do? Re-install? Good luck with that! Been there, tried that... And it doesn't work! And the reason for that? The password you provided to Outlook, is inside the Stored Credentials store and still active. So lets do it a much "easier" way! It is just well hidden, and not so well known.
Create Office 365 App-password for accounts with MFA
Go to: https://account.activedirectory.windowsazure.com/AppPasswords.aspx
Click the blue Create button.
In the new dialog pop up: Choose a name.
Click Next.
Click Show Password to unhide the password.
Copy the newly created password and keep it safely stored away.
Note: The password gets only shown once!
Continue to the next section: Remove locally stored password.
Remove locally stored password credentials
Now remove the stored password that you've used during the install.
- Click Start > Control Panel > User Accounts > Credential Manager.
Note: If 'View by' is set to Category, click User Accounts first, and then click Credential Manager.
Select the Windows Credentials option. Locate the set of credentials that has either Outlook or Microsoft Office in the name and then expand the corresponding folder.
Then click Remove from Vault or Remove (depending upon which version of Windows you are running).
Repeat step 3 for any additional sets of credentials that have the word Outlook or Microsoft Office in the name. (and resembles the account-name you tried to remove)