Prevent Double Booking on a Sharepoint Online Calendar

Question

I have created a "Calendar" app on Sharepoint Online for meeting room bookings.

However, I cannot prevent double booking (the same date and time can be booked for different people without even notifying them).

I don't think the "Resource Scheduling Settings" feature is still available in Sharepoint Online. Most probably it has been deprecated.

I read somewhere that this might be resolved by creating a validation formula.

Any idea what might this formula be if we work on the "Start time" and "End time" columns ?

Answer 1

@Dr. Geek

It cannot be achieved by set a validation formula.

A common workaround would be using Power Automate to check after the new event creation, delete the duplicate entry if any. Here is an example: Prevent double booking SharePoint calendar for the day.

In addition, there is a PowerApps Office Template named Book a Room that might do some help on this scenario. Reference: Office Template: Book a Room now available.

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