Airdrop not working with Catalina OS

What's the problem, exactly? There is no known problem with AirDrop. Until you tell us what the problem is that you are having, we cannot know if there is a fix.

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AirDrop Tips for Mac and iOS Users

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Thank you for your understanding and support.

If your mac is somewhat old - older than maybe 2012 - you can’t anymore. Up to and including Mojave there was a “look for older macs” in the AirDrop window, that, well, allowed for looking for, and connecting to older macs. If your older mac required this in order to be visible to your newer mac running Mojave, then it will not work with AirDrop with a Catalina mac.