I don't see Airdrop in my side finder window; so I'm assuming there has to be a mac in vicinity in order for it to appear? Sharing is turned on.
Finder > Preferences > Sidebar > AirDrop check box.
Airdrop is there but to use it you need turn on wifi and have macs around.
Check the box.
I have an early 2008 iMac, it may be Airdrop only works starting early 2009 imac
That is correct.
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