Unable to verify Microsoft accounts in the Mac Mail app

[Mity]

I just got a new Mac and for some reason I am not able to install my Outlook mail accounts (any of them) but Google accounts are working fine. I am able to access my Outlook accounts via the web as normal. I am on macOS Sequoia 15.7.1.

Anyone having the same issue?

 

[Beowulf404]

Yes, I have experienced what sounds like the same issue, although without knowing more about your specific Outlook accounts I cannot be certain. In my case, the email accounts in question were hosted on Microsoft Exchange Server with 2 factor authentication. I believe that the issue may also affect Microsoft365 accounts. In this case you may be actively prevented from accessing with the Apple Mail client depending on the organisation's own security arrangements e.g. using 2FA. This security did not affect email access to the same accounts using Apple Mail on my iOS devices (iPhone) as 2FA authentication pop-ups with password and Face ID are well integrated into iOS.
Depending on your organisation, it may be that the most rapid (but perhaps not the most elegant) solution for you is to use MS Outlook for those specific Outlook accounts, for which you will need to generate an App Specific Password. At least then you will obtain immediate access to your emails on your new Mac, albeit using two different email clients.

Sign in to apps with your Apple Account using app-specific passwords - Apple Support

App-specific passwords allow you to securely use your Apple Account to sign in to apps made by developers other than Apple.

support.apple.com

If another member has a less clumsy solution, or if I have misunderstood the problem, then I too would be interested to learn.

 

[Mity]

Yes, I have experienced what sounds like the same issue, although without knowing more about your specific Outlook accounts I cannot be certain. In my case, the email accounts in question were hosted on Microsoft Exchange Server with 2 factor authentication. I believe that the issue may also affect Microsoft365 accounts. In this case you may be actively prevented from accessing with the Apple Mail client depending on the organisation's own security arrangements e.g. using 2FA. This security did not affect email access to the same accounts using Apple Mail on my iOS devices (iPhone) as 2FA authentication pop-ups with password and Face ID are well integrated into iOS.
Depending on your organisation, it may be that the most rapid (but perhaps not the most elegant) solution for you is to use MS Outlook for those specific Outlook accounts, for which you will need to generate an App Specific Password. At least then you will obtain immediate access to your emails on your new Mac, albeit using two different email clients.

Sign in to apps with your Apple Account using app-specific passwords - Apple Support

App-specific passwords allow you to securely use your Apple Account to sign in to apps made by developers other than Apple.

support.apple.com

If another member has a less clumsy solution, or if I have misunderstood the problem, then I too would be interested to learn.

These are actually my personal Outlook accounts, not professionally managed Exchange accounts, but I believe Outlook accounts are supported in the "MS Exchange" option in the Mail app on Sequoia. I don't have 2FA enabled on these accounts they also don't have passkeys or anything else preventing setup. The accounts are working fine on my other M4 Mac. But I bought an M4 Air yesterday, immediately upgraded to the latest Sequoia version, and noticed that only my Google accounts are being linked. I did a fresh install - I did not copy anything over from my M1 MBA.

I remember a few years ago this was a problem around Catalina and the way I solved the problem was changing the default browser to Safari from Chrome. I did this again but it didn't work.

Edit: I just checked these same Outlook accounts on my M4 MBP and they are indeed syncing just fine there. The M4 MBA is the issue and I'm not sure why.