Thank you for reaching out to Atlassian Community!
Searching using the details you provided, I’m afraid to say that the only way to integrate an Outlook calendar is by using an add-on.
Here are some add-ons that I found that may help you:
You can find more options in our Marketplace:
Hello Insight users, As part of our (Mindville's) acquisition by Atlassian, our training team is looking to build some new Insight training materials and we want to hear from you! ...
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