Need Modern Authentication (OA2) email requirement to be clarified and simplified

By now we all know about Gmail recently cutting off support for less secure email apps. My gmail is my secondary email so I began using their web app to read my mail. That was no biggie for me. Now, Microsoft has sent notice they are following suit as of this September, pushing people to use a more secure protocol. I need to understand both for myself and how I advise others. I am totally confused so will someone verify my points of understanding regarding certain email apps when using @outlook.com and @hotmail email accounts and answer my questions about them.
I am using this article as my point of reference and its terminology is over my head.

1. Outlook in Office 2003, 2007, and 2010 will not work once OA2 goes into effect in September. Outlook 2013 requires a registry fix to make it work. What about OFC2016? What do I have to do with it?

OA2 is supported in OFC2019, OFC2021, MS365(which includes Office on the web) and Outlook.com users, but the application must be registered with a token. How, exactly does one do this? Many people log directly into into outlook.com? Would one register and get a token for a browser in this case? What special email settings need to be changed in these apps to make it work?

2. Users of the latest version of Thunderbird can still get @outlook.com and @Hotmail.com email. What special setting in TB would apply here. Would I register Thunderbird with a token and how?

3. Windows mail app in Windows 10 and 11 will continue to work, but in Windows 10 Mail client one has to remove and add back the account, choosing Office 365 as the account type. Does one have to do anything in Windows 11 Mail app the same way?

4. Are there any other third party mail apps for WIndows besides Thunderbird that support OA2?

5. Apple and Android mobile users will have to move to Outlook for iOS and Android or another mobile email app that supports Modern Auth. If they currently use their mobile phone's native mail app, they will have to remove their account and reestablish it as Ofc365 account type. Is that all they will need to do?

I know I'll end up having more questions about this because right now it is as clear as mud. Y'all help me to understand.

Have a look at these articles, hope you find some respite

@Ruben Your second link won't load. Attempt to fix it, please. I had come across one of those links in my reading but I've read so many articles now that nothing makes sense any more. I've gone into information overload.

Thank you.

Steps to configure Thunderbird for modern authentication

Thunderbird - Configure OAuth2 (Modern Authentication)

At the bottom of the page you will find a link to O365 Transition to modern authentication after click on that link you can find the steps for Office 365 (Outlook for Windows)

Huge p•i•t•a is what it is!

Edwin said:

p•i•t•a

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Yeah. I have about 40 people that I try to help. Their ways of accessing email vary from Webmail, the OS email app, the apps on their phones, old Windows Live Mail, and every single version of MS Office Outlook all the way back to 2003. Not a single one of them use Office365, nor do I. My phone is going to light up like a Christmas tree when all this change goes into effect. If I can't understand it, I can't expect them to.

@glasskuter, Here's a very important paragraph in the article you linked...

One thing you need to remember that enabling Modern Authentication for Exchange Online using the Set-OrganizationConfig parameter only impacts Outlook for Windows. Outlook on the Web, Exchange ActiveSync, Outlook Mobile or for Mac etc., will continue to authenticate as they do today and will not be impacted by this change.

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It only impacts those using the desktop Windows app. And those with exchange accounts.

glasskuter said:

I need to understand both for myself and how I advise others. I am totally confused so will someone verify my points of understanding regarding certain email apps when using @outlook.com and @hotmail email accounts and answer my questions about them.

Click to expand...

If you are not using the Windows app, you will (should) not be impacted. Those of us with exchange accounts (me) may be affect if you're not using OA2. I am (via Okta) per my school's requirement for my school account, so no issues there.

Once Modern Authentication is turned on in Exchange Online, a Modern Authentication supported version of Outlook for Windows will start using Modern Authentication after a restart of Outlook. Users will get a browser-based pop up asking for UPN and Password or if SSO is setup and they are already logged in to some other services, it should be seamless.

If the login domain is setup as Federated, the user will be redirected to login to the identity provider (ADFS, Ping, Okta, etc.) that was set up. If the domain is managed by Azure or set up for Pass Through Authentication, the user won’t be redirected but will authenticate with Azure directly or with Azure on behalf of your Active Directory Domain Service respectively.

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So, the way I understand it, is this is mainly for desktop apps with Azure/Exchange accounts connected - those of us (me) using Office 365 from a school or business with an email account connected to an exchange server.

Thanks @Dru2. What concerns me is this point you highlighted above. only impacts Outlook for Windows. Outlook on the Web.

I interpreted Outlook for Windows to mean the different versions of Outlook in MS Office 2003-2016, but are you saying this is referring to the Windows Mail app?

The mention of outlook on the web is throwing me as well. I don't know if this is referring to the Outlook webmail or MS 365 Outlook.

So far, only 2 people I know have contacted me that they got a notice from MS that they had to change mail apps. I got one myself. Both preferred the webmail interface over using the mail app in windows, so that's what I set up for them. Then I got to questioning if I steered them in the right direction and that there is something more I should do so that webmail will continue to work after this all finalizes.

MS should be hung for using the term 'outlook' for different applications. It's just one of those things that confuses users for no good reason.

glasskuter said:

Thanks @Dru2. What concerns me is this point you highlighted above. only impacts Outlook for Windows. Outlook on the Web.

I interpreted Outlook for Windows to mean the different versions of Outlook in MS Office 2003-2016, but are you saying this is referring to the Windows Mail app?

The mention of outlook on the web is throwing me as well. I don't know if this is referring to the Outlook webmail or MS 365 Outlook.

Click to expand...

When I say Outlook, I mean the "Office" app NOT the Windows Mail app. Outlook on the web to me means Outlook.com.

glasskuter said:

So far, only 2 people I know have contacted me that they got a notice from MS that they had to change mail apps. I got one myself. Both preferred the webmail interface over using the mail app in windows, so that's what I set up for them. Then I got to questioning if I steered them in the right direction and that there is something more I should do so that webmail will continue to work after this all finalizes.

Click to expand...

Are you, and the other person that got the email, using the "Windows Mail" app?

If so, perhaps there does need to be some clarity in what the name "Outlook" and Outlook on the web, means. But for me it's pretty obvious the article means Outlook office app, and Outlook.com, since the OA2 requirement was issues in 2019.... before Windows 11 and the "what should we call Windows Mail" controversy. And as far as I know Microsoft is STILL calling Windows Mail... "Mail".

From: Sriraman M S <notifications@github.com>
Sent: 25 July 2022 12:29
Subject: Re: [MicrosoftDocs/microsoft-365-docs] Modern OA2 Authentication (Issue #9187)

Thank you for your feedback. I have checked and OA2 is supported on office 2021. The impact will be on the earlier versions of office only and not on 2021.

Hope this helps!

Thanks
Sri