Applies ToOutlook for Microsoft 365 Outlook 2016 Outlook 2013 Outlook.com

Last Updated: June 10, 2024

Issue

For many years, applications have used Basic Authentication to connect to servers, services, and API endpoints. Basic Authentication simply means the application sends a username and password with every request, and those credentials are also often stored or saved on the user’s device. Traditionally, Basic Authentication is enabled by default on most servers or services and is simple to set up. While Basic Authentication was the standard at the time, Basic Authentication makes it easier for attackers to capture user credentials, which increases the risk of those stolen credentials being reused against other endpoints or services.   

Basic Authentication is an outdated industry standard. Threats posed by it have only increased with time and we have already deprecated Basic Authentication across numerous products. For more information, go to Improving Security - Together. There are better and more effective user authentication alternatives.

Transition Timeline

June 11th, 2024  

  • Basic Authentication end of support timeline communicated

End of June 2024 

  • Outlook account actively using Basic Authentication contacted via email

September 16th, 2024 

  • Basic Authentication no longer available to access any Outlook account

Basic Authentication interim experience

Until September 16th, users signing into Outlook.com through Basic Authentication may experience recurring password prompts in Outlook and other third-party email applications. This is a known issue. After September 16th, users attempting to connect their Microsoft accounts through Basic Authentication will fail to do so.

Recommended User Actions

In preparation for the upcoming Basic Authentication deprecation, here are the ways users can update their accounts to use Modern Authentication. 

If you use Outlook for Windows

Outlook supports Modern Authentication in all current Microsoft 365 subscription SKUs and Outlook 2021 LTSC (any SKU with build 11601.10000 or higher) when connecting directly as Outlook.com. If your Outlook is configured to connect to Outlook.com using POP or IMAP, Modern Authentication is not supported. This means that when Basic Authentication is fully deprecated, it will no longer connect.  For this scenario, you have a few options:

Option 1: Get a newer Outlook email app which supports Modern Authentication

If your Outlook client does not support Modern Authentication, you will need to upgrade to the latest version and then setup using Outlook.com Sync. You can either purchase a new Outlook License, use the Outlook that is included in your Microsoft 365 subscription, or download Outlook for Windows for free.  

Option 2: Switch to Outlook.com/Exchange Syncing

Instead of using POP/IMAP and SMTP, create a new Outlook Desktop profile and then add your Outlook.com account using automatic account configuration, which will add the account with Modern Authentication. To do this, please use the following guidance:

  1. Create a new Outlook Desktop profile. For more information, please go to Create an Outlook profile.

  2. Add your Outlook.com account. For more information, please go to Add an email account to Outlook.

The following versions of Outlook Desktop do not support Modern Authentication for Outlook.com:  Outlook 2007, Outlook 2010, Outlook 2013, Outlook 2016 MSI, Outlook 2019 LTSC. Any release of Outlook Desktop with a version less than 11601.10000 does not support Modern Authentication for Outlook.com.

Outlook apps are available for free and can be downloaded directly from the Microsoft Store on Windows, the Mac App StoreiOS App Store, or the Google Play Store.  

After your download the new email app, add your accounts and they will all be configured to use Modern Authentication and sync properly, helping keep them safe.

If you use Mozilla Thunderbird: 

Mozilla Thunderbird does support Modern Authentication and it is recommended that you ensure you switch to use those settings. Any account that you add to Thunderbird will now automatically setup using the proper settings. You have the following options:

Option 1: Update Current Settings

  1. Change Thunderbird's server settings:

    1. Select  > Account Settings.

    2. In the left pane, select Server Settings for your Outlook.com or Hotmail.com account.

    3. For Authentication method, select OAuth2 (instead of Normal password).Modern auth in Outlook Mozilla step 1

  2. Change Thunderbird's authentication method for sending messages (SMTP):

    1. Select > Account Settings.

    2. In the left pane, select Outgoing Server (SMTP).

    3. In the right pane, select your Microsoft account and then Edit… .Modern auth in Outlook Mozilla step 2 C

    4. For Authentication method, select OAuth2 (instead of Normal password).Modern auth mozilla step 2 SMTP Server

    5. Select OK to save your changes.

Option 2: Remove Current Account and Re-Add  

If you remove your current account from Thunderbird and then re-add it, the proper settings will be detected, and you will just need to sign in to be properly configured with Modern Authentication and the proper server settings.

If you use Apple Mail:

Apple Mail supports Modern Authentication by default when you setup the account as Outlook.com. If you use Apple Mail and you are seeing password prompts or connection errors, this is most likely happening because your account got configured as basic authentication. To mitigate the issue, remove the account and add it back as Outlook.com:

  1. Go to Settings > Mail > Accounts.

  2. Tap the email account you want to remove from your iPhone, then tap Delete Account. For more information, please go to Add and remove email accounts on iPhone.

Add your account back to Apple Mail: 

  1. Go to Settings > Mail.

  2. Tap Accounts, then tap Add Account.

  3. In the Add Account dialog, choose Outlook.com.Apple mail add Outlook.com to iPhone

If removing and re-adding the account does not address the issue, do the following: 

  1. Remove the account again.

  2. Go to Settings > Safari, then tap Clear History and Website Data.

  3. Reboot your iPhone.

  4. Add the account back and proceed through the Outlook.com account sign in flow.

If you use another email application: 

Always check the add account steps to look for Outlook.com and use it if that option is available. If Outlook.com is not an option, you will want to contact the application's support to confirm that they support Modern Authentication against EAS, POP, IMAP, and SMTP.

If the application does not support Modern Authentication, downloading Outlook is recommended. As a reminder, all users can download Outlook for free and it works with most email services. Outlook can be downloaded directly from the Microsoft Store on Windows, the Mac App StoreiOS App Store, or the Google Play Store.

For additional support or questions, please refer to the Answer forum thread , Microsoft Community.

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See Also

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