In Microsoft Outlook 2016 for Mac, you are repeatedly prompted for authentication while you're connected to your Office 365 account.
This issue occurs because of the presence of duplicate tokens in the keychain.
Office for Mac that comes with a Microsoft 365 subscription is updated on a regular basis to provide new features, security updates, and non-security updates. The following information is primarily intended for IT professionals who are deploying Office for Mac to the users in their organizations. Email message body is blank in Outlook.; 2 minutes to read; S; Applies to: Outlook 2016, Outlook 2013, Microsoft Outlook 2010, Microsoft Office Outlook 2007, Microsoft Office Outlook 2003; In this article. Original KB number: 2854787. When you view an email message in Microsoft Outlook, the message body is blank.
To resolve this issue in Outlook 2016 for Mac, install the February 2017 Outlook update (version 15.31.0) from the following Office website:
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.
Note
These steps affect all Office applications that use modern authentication.
Quit Outlook and all other Office applications.
Start Keychain Access by using one of the following methods:
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:<GUID>, and then press Delete.
In the search field, enter office.
Select the items that are named Microsoft Office Identities Cache 2 and Microsoft Office Identities Settings 2, and then press Delete.
Quit Keychain Access.
Note
When you start Outlook, you are prompted to authenticate.