Outlook / Office 365 Sign-in password prompt window.

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Hello Kenneth Sanchez,

Have a good day. Thanks for your post in forum.

Regarding your description, When Microsoft Outlook for Mac connects to an Office 365 account, Autodiscover is redirected from HTTP to HTTPS, and you may receive this kind of warning message.

When this warning message occurs, you may select “Always use my response for this server” and then click “Allow” in order not to be asked about this specific server again for this Outlook for Mac profile.

On the other hand, kindly try to resolve from the following steps.

1. Quit Outlook if it's running.

2. Open Terminal using one of the following methods:

·         With Finder as the selected application, on the Go menu click Utilities, and then double-click Terminal.

·         In Spotlight Search, type Terminal, and then double-click Terminal from the search results.

3. Enter the following command in the Terminal window, and then press Enter.

       defaults write com.microsoft.Outlook TrustO365AutodiscoverRedirect -bool true

4. On the Terminal menu, click Quit Terminal.

Also, if the issue still persist in Outlook for Mac, we have dedicated support team for Outlook for Mac, which is specializing to handling Outlook for Mac related issue. So, kindly use the contact support option to get the dedicated support within the Outlook for Mac for further assistant. For Outlook for Mac support > open Outlook and select Help > Contact Support.

For your reference: Contact Support feature in Outlook for Mac.

Your cooperation will be highly appreciated.

Regards,

Darpan

Hello Kenneth Sanchez,

Have a good day. Thanks for your reply.

Regarding this issue, kindly try to 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.

Hope above information will help you.

Regards,
Darpan