Outlook on Mac, getting Error 50089 - Flow token expired - Authentication Failed multiple times daily

Question

Referred to this forum to post this question from answers.microsoft.com post

Hello,

We have a Mac OS user at our company that has been getting repeated prompts for their password daily from Outlook. These issues started a few weeks ago. When looking in Sign-in logs in Entra we found that each time they are prompted there is a Sign-in failure with error code '50089 - Authentication failed due to flow token expired.' Once they enter their password it lets them back in without any issue and we see a successful Sign-in in the logs right after the failure. Researched this issue on the forums and attempted the following troubleshooting steps without any success:

Updated the OS to the latest update.

Logged out of all Office applications and back in.

Cleared Keychain Access with the following steps:

Quit Outlook and all other Office applications.

  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.
              
                 In the search field in Keychain Access, enter **Exchange**.
                 
                    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.
                    
                       In the search field, enter **adal**.
                       
                          Select all items whose type is **MicrosoftOffice15_2_Data:ADAL:

Answer 1

Hi @Kevin Hajny

Thanks for reaching out to Microsoft Q&A

Based on what you described, you have already followed this workaround is that right?

https://learn.microsoft.com/en-us/outlook/troubleshoot/sign-in/repeated-prompts-authentication

The error you are getting is because the access token has expired, which should be expected as it has a ~1 hour duration, but the client application should be able to request a new access token on the backend without user intervention.

Could you please confirm if you have installed the latest updates for the Outlook 2016?

https://learn.microsoft.com/en-us/officeupdates/release-notes-office-for-mac?redirectSourcePath=%252farticle%252fRelease-notes-for-Office-2016-for-Mac-ed2da564-6d53-4542-9954-7e3209681a41

Also, in the sign in logs, can you see any Conditional Access policy applied to this sign in attempt?

Thanks,

Fabio