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When creating a meeting, you can enable disable the option Enable join before host which will allow participants who have your meeting information to join the meeting before you have started it. This can be helpful if you have a trusted group of participants who you would like to be able to communicate before you have joined, but disabling this option will ensure that you have started the meeting before others can join (and cause trouble). This is especially important for recurring meetings that use the same link, Meeting ID, and password - as anyone with this info could join your meeting at any time.
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