The administration and maintenance of Microsoft Exchange Server to ensure secure, reliable, and efficient email and collaboration services across an organization.
Hi @Chris ,
Any update here about your question, feel free to share your progress here if any. Some additional information below:
As I know, the online archive feature is available to some specific version of Outlook, it's recommended to follow this document to check if your Outlook 2021 could meet the requirements of license. I used to see the user using Office Home & Business version encountered the same problem.
If that's not your case, based on my research, I found a related document about How to troubleshoot an Exchange Online Archive mailbox that is not displayed in Outlook, please follow it to check if that could work for you.
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