Hi @Lmag ,
Welcome to our forum!
Does the "Track email open rates" option not appear when I select any of the eligible sent emails?
And I found that after selecting the sent email in Outlook > click on the Viva Insight add-in, and when I scroll down, the "Checking for insights" load will appear, and then the "Track email open rates" option will appear, please make sure you have slid to the bottom.
Hope to help you!
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