Airflow can't connect to my Chromecast / Apple TV
If Airflow sees your device but you get error while connecting, it's almost always caused by a third party firewall software or a VPN. Please check any third party firewall software or VPN that might interfere.
If Airflow sees your device but you get error while connecting, it's usually caused by a third party software that blocks the connection.
See if you have any of the following software installed, and if so, make sure it is configured to let Airflow make the connection: Radio Silence, Lulu, Little Snitch, Murus, Vallum, Hands Off, Netiquette, TCPBlock.
Alternatively, this may also be caused by certain VPN software.