SharePoint Calendar

There is no direct way to add events to a SharePoint calendar from an Outlook calendar invite out of the box, but there are ways to achieve this functionality.

• Sync Outlook Calendar with SharePoint Calendar
• Using Power Automate (Flow) to Automate Event Creation
• Using Outlook's "Add to Calendar" Feature. For a simpler, but still somewhat manual, approach, you can take advantage of Outlook's "Add to Calendar" feature.

For classic calendars, syncing via Outlook is possible, but modern SharePoint calendars require other methods.

Power Automate offers the most powerful, customizable solution for integrating Outlook events into a modern SharePoint calendar automatically.

Regularly check Microsoft’s updates, as SharePoint Online is constantly evolving, and new features may simplify this process in the future.

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Hope this will help you.