Users with older versions of Outlook, which is any version from Outlook 2019 and older, may be affected if they have an MSI or LTSC version that does not receive updates. If your Outlook 2016 or newer recieves updates (should be 170000.***** or higher if fully updated). You will no longer be able to set up a POP or IMAP account in classic Outlook to connect to Outlook.com; you will need to add it using File > Add Account and let auto account set up add the account as a Microsoft Exchange account.
Classic Outlook desktop versions older than 11601.10000 do not support Modern Authentication for Outlook.com. Users will need to use Outlook on the web, new Outlook, or a third-party mail client, such as  eM Client and Thunderbird. Both support modern authentication using POP or IMAP.
From Microsoft: The following versions of Outlook Desktop do not support Modern Authentication for Outlook.com: Â 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.
Note: if you are using a third party mail app, either on desktop or mobile device, and Outlook.com stops syncing, first remove the account and add it back. If the client supports modern auth, it will add the account back using modern auth. If you are using Thunderbird or eM client, you can update the account authentication without removing the account.
By the end of June 2024, users still using basic auth to connect to Outlook.com accounts will receive an email notifying them one or more devices is using basic authentication. On September 16th, 2024, users will be unable to use Basic Authentication to access any Outlook account.
Those most affected by this change will be users of classic Outlook 2007 to 2019. It is recommended to use Microsoft Exchange services to sync classic Outlook and Outlook.com, not POP or IMAP (which will no longer work to connect Outlook.com to Outlook.)
Any app that brings up the Microsoft login dialog you see when you sign in using a browser will work after September 16. That screen means it uses modern auth (also known as oAuth2.) If you have a normal password dialog when you sign in, the app does not support modern auth.
If you have 2-step verification enabled and are using an app password, that app is using basic auth. App passwords will be disabled / removed when basic auth is turned off.
Microsoft has stated that users signing into Outlook.com using apps that use basic auth may have repeated password prompts in their email apps. Consider it a warning that the app is using basic auth. After September 16th, these apps will not connect to Outlook.com.
User Questions
Q: Is my Gmail or other non-Microsoft account affected by this change?
A: No. Only Outlook.com accounts, including Hotmail, live.com and MSN addresses. Users with custom domains from one of the defunct custom domain programs are also affected.
If you have the account added to Outlook as a Microsoft Exchange account and are using a version of Outlook currently in support, you are all set.
If the account is added to any version of Outlook Classic as a POP or IMAP account, it will stop working in September. If you have a supported version of Outlook, you’ll either need to remove the account and add it back using auto account setup so it’s added as an Exchange account, or you will need to use another mail app. Both eM Client and Thunderbird support modern authentication using POP or IMAP.
If you are not using a supported version of Outlook Classic – this includes Outlook 2013 and all older versions, volume license, some single purchase retail licenses – you need a new mail app, either a modern version of Outlook or a different client.
If you are using Windows Live Mail, it’s past time to ditch it. eM client is a good replacement and can import your mail from WLM.
Other older email clients, such as Apple mail on older macOS or iOS are not supported. If you get repeated password prompts, it is using basic auth. If you have a newer iPhone or iPad, it supports modern auth but if the account was added to the app years ago, you'll need to remove the account and add it back. Apple will not automatically switch the account to use modern auth.
Q: I have my Gmail account configured to download my Outlook.com mail. Will this affect me?
A: If you have the outlook.com account added to Gmail as a POP account, it will quit working. If you added it as a gmailify account, it will continue to work as gmailify uses modern auth. However, you can only use gmailify with one account.
More Information
More information from Microsoft:
Modern Authentication Methods now needed to continue syncing Outlook Email in non-Microsoft email apps - Microsoft Support
Hi Diane!
When I use Outlook mail to send, the length of the lines are well over 200 characters, so I have to do hard returns. .
When I go to Outlook Options / Mail / Message Format, I have "auto wrap text" set at 40 characters.
What else could be driving this extreme length of my email lines?
thank you very much!!
The lines should be wrapping automatically in the window of most (if not all) email clients, so on need to mess with line lengths.
The screenshot has my settings, which wrap correctly.
Thanks for your message!
This is the setting I have always had and never a problem. My setting is still like this but it does not break. There must be something else overriding this issue. Any ideas? thanks!!
Is it wrapping when you are composing but not for the recipient?
HI Diane - I am super desperate (already posted on Microsoft forum but still to no avail!)
I have a Microsoft 365 subscription but my Outlook kept asking for a password for my Hotmail email (sometimes it would accept it, sometimes not so I know it was not the wrong password). Also, on web browser it works fine no issues. But I like to have it all in outlook as I have both my Hotmail and my work email in the same place which is much easier for me.
I ended up changing my Hotmail password in the hope this would help but it didn't. I then deleted the Hotmail account from Outlook in the hope that when I added it back in, it would work. But no....now I cant add it back in because it still says my credentials are wrong?!!
Please help me. I had someone remotely connect to my computer yesterday for 3 hours and they couldn't work it out and I am at the end of my tether (in the middle of a home sale and I REALLY need access to my email right now!!)
Thank so much
Mané
>>
my Outlook kept asking for a password for my Hotmail email (sometimes it would accept it, sometimes not so I know it was not the wrong password). Also, on web browser it works fine no issues.
>>
That sounds like Outlook is using basic auth.
You are using a current version of Outlook from the subscription? Outlook 2013 and older are no longer supported with outlook.com accounts, along with older MSI versions of Outlook 2016.
Are you adding the account as an exchange account? POP and IMAP to outlook.com are no longer supported. You need to use autoaccount setup - using control panel > mail will no longer work for Exchange online accounts.
I'm also having the same problem, and followed the same steps of changing Hotmail password, removing & re-adding account in Outlook. I'm using Outlook 2021 Pro LTSC.
What is your build / version number? Not that it matters:
Basically, none of the volume license versions support modern auth. You need a version at or above 11601.10000. Retail versions of Office 2021 do get updates and support modern auth.
Mane
I had the same problem and just solved it. It did involve a registry string alteration (via the Registry Editor).
HKCU/SOFTWARE/Microsoft/Office/16.0/Common/Identity
EnableADAL was set to 0. Once I changed this to 1, re-opened Outlook and then re-attempted to add the Hotmail account, it was successful.
I do hope this helps for you.
Diane , I'm confused. I was of the understanding that Oauth2 was enabled in Outlook 2013 by setting the registry keys described here - https://learn.microsoft.com/en-us/exchange/troubleshoot/administration/modern-authentication-configuration . So why will Outlook 2013 no longer connect to Outlook.com with EAS?
I'm not sure why they removed 2013 from the list, unless it was just because its old and no longer supported.
Seems helpful, but I don't know what POP and IMAP are. I don't know what you mean by a Microsoft login dialog and I don't know if I have two-step verification enabled, nor how to find out any of these things. I have a live.com account on my PC and I just click on the tab. My Huawei mobile can access my emails as can my tablet and iPhone. Should I download eM client on PC, phones and/or iPad? Will everything then happen automatically? I suspect not.