Using the New Outlook for Mac features in business environments
Hi Jane
Based on your description, I understand that you can receive emails, but you are unable to send emails from Outlook on your iMac, and messages are stuck in the Outbox while the issue does not occur on your other devices.
To better understand your issue, could you please provide more detail:
-Could you check if Outlook is set to “Work Offline” on the iMac?
-Which version of Outlook you are using on the iMac
-When the send fails, do you receive any error message? If yes, please share the exact error
-Could you provide a screenshot of the cloud icon with the strike-through next to the mailbox name? If yes, you can send the screenshots via private message to avoid exposing any personal or organizational information publicly.
-Have you tried signing out and signing back in to the account in Outlook on the iMac?
-Could you try creating a new macOS user profile on the iMac to test whether the issue is related to the current user profile?
For your reference: Add a user or group on Mac - Apple Support
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Please understand that our initial reply may not always immediately resolve the issue. However, with your help and more detailed information, we can work together to find a solution.
I look forward to your update.
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