Glad to hear this issue has been resolved!
Thanks for the sharing.
However, due to a recent update in forum policy, the question author now is not able to accept their own answers.
So I have written a brief summary of the solution this issue. Please feel free to accept it as the answer, which would benefit others who also has similar issues in forum.
[Having trouble getting my Outlook Add-in manifest to work]
Issue:
When developing the add-in, I couldn't figure out how to organize my list. I have a development tenant to which I want to push this application in the Microsoft admin center, but every time I try to upload my manifest, it doesn't work.
Solution:
Ok I was able to get the manifest to upload and deploy to my local outlook client and I see it with my test account. This question is resolved.
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