I was trying to Airdrop a file from my Iphone to Macbook Air after upgrading to HighSierra. I tried all options but got crazy as only my Macbook air was not listing while same time my Macbook Pro was listing which had a fresh install of HighSierra. If any one is facing the same issue they can try the following.
Goto System Preference > Security & Privacy > Firewall > Click the lock to make changes > click on Firewall options > uncheck the Block all incoming connections check box
Airdrop not working after upgrading to MacOS HighSierra?