Authentication loop in Outlook Mac

Question

Hello all

I have a totally infuriating problem which is that when I log in to my Office 365 account on my Mac, using the outlook client (16.58), I get stuck in an authentication loop.

I log in, verify via the Microsoft Authenticator app, then immediately it triggers re-authentication over and over.

I found some advice to delete certain keychain items, which I attempted but they would not delete. I tried removing and reinstalling Outlook but it didn't help.

I badly need to fix this and would very much welcome some help from anyone wiser and smarter than me!

Thanks

Dominic

Answer 1

Hi Kerry, I'd really appreciate any more ideas if you have them!

Dominic

Answer 2

Dear Dominic Young，

Thanks for choosing Microsoft community!

I have read your question carefully and done some research, please kindly refer to following suggestions:

This issue occurs because of the presence of duplicate tokens in the keychain.

To work around this issue, delete any cached passwords for your account, and also delete any modern authentication tokens from the keychain. To do this, follow these steps：

1. Quit Outlook and all other Office applications.
2. Start Keychain Access by using one of the following methods:
   • Select the Finder application, click Utilities on the Go menu, and then double-click Keychain Access.
   • In Spotlight Search, type Keychain Access, and then double-click Keychain Access in the search results.
3. In the search field in Keychain Access, enter Exchange.
4. In the search results, select each item to view the Account that's listed at the top, and then press Delete. Repeat this step to delete all items for your Exchange account.
5. In the search field, enter adal.
6. Select all items whose type is MicrosoftOffice15_2_Data:ADAL:<GUID>, and then press Delete.
7. In the search field, enter office.
8. Select the items that are named Microsoft Office Identities Cache 2 and Microsoft Office Identities Settings 2, and then press Delete.
9. Quit Keychain Access.

Please pay attention to this: These steps affect all Office applications that use modern authentication.

Hope this help you, if there is any deviation in my understanding, please forgive me and provide me with more details. I am more than happy to continue to help you. I wish you a smooth new year and all the best!

Best regards,

Kerry

Answer 3

SO I can delete the Exchange credentials (there's only one) but the ADAL stuff isn't quite what you described and I can't delete it... any clues? None of the three entries below can be deleted from my Keychain...

Answer 4

Thanks Kerry, this is the process I tried before but it didn't work. I'll try again on a safe mode reboot to see if it works!

I'll let you know

Kind regards

Dominic