This method is for one-off use cases only (like testing the app).
For official deployments, see: Deploy Outlook to Staff
Add-in can be installed directly into Outlook using this special Microsoft "sideloading" link: https://aka.ms/olksideload
Wait a second for the Add-ins dialog to show up, then go to My addins — Custom — Add Custom Add-in and upload the .xml file provided to you by TonicDM.
After closing the Add-ins dialog box refresh the browser and the add-in will be available in the Apps list.
