Hi @Ian
Welcome to our forum!
Looks like your issue is more related to Outlook development, please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client.
Based on my search, to deploy and install add-ins, you can refer to this article:
https://learn.microsoft.com/en-us/office/dev/add-ins/outlook/testing-and-tips.
By the way, in order to better solve the problem about development, you can get more professional advice under this Office Development tab.
Thanks for your understanding!
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