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![Outlook For Mac Office 365 Outlook For Mac Office 365](/uploads/1/2/6/3/126348174/331166966.png)
Symptoms
In Microsoft Outlook 2016 for Mac, you are repeatedly prompted for authentication while you're connected to your Office 365 account.
Cause
This issue occurs because of the presence of duplicate tokens in the keychain.
Outlook For Mac Office 365 Setup
I have recently installed Office 365 for Mac and am using Outlook for my mail program. I upgraded from Outlook 2011 for Mac. I cannot find a way to view the headers on incoming mail as I could in 2011. Microsoft is bringing its sync technology that’s used on Outlook for iOS and Android and Windows Mail to Outlook for Mac. It means Office 365, Outlook.com, and even Google accounts will sync.
Resolution
Outlook for Mac support tools. 11/4/2019; 3 minutes to read; Applies to: Outlook for Mac for Office 365; In this article Summary. This article describes some useful tools for Microsoft Outlook for Mac. More information Outlook Search Repair. The Outlook Search Repair tool repairs search results within Outlook. Note: To see how to set up Full Access permission, see How to grant Exchange and Outlook mailbox permissions in Office 365 dedicated. Checking the setting Sync shared mailbox will allow Outlook to synchronize the shared mailbox without requiring the user to click Send/Receive.
To resolve this issue in Outlook 2016 for Mac, install the February 2017 Outlook update (version 15.31.0) from the following Office website:
There are three types of setup of Outlook 2013 to work with Office 365: Automatic Account Setup; Manual IMAP Setup; Manual Exchange Setup Automatic Account Setup. Begin by launching Microsoft Outlook 2016 for Mac. On the menu bar at the top of the screen, click 'Outlook' and then click 'Preferences'. On the window that pops up, click 'Accounts'.
Workaround
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
Outlook For Mac 2011 Office 365
These steps affect all Office applications that use modern authentication.
![Outlook For Mac Office 365 Outlook For Mac Office 365](/uploads/1/2/6/3/126348174/331166966.png)
Outlook For Mac Office 365
- 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:<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.NoteWhen you start Outlook, you are prompted to authenticate.