Windows UI will not connect, only notifies:
“Waiting for ZeroTier system service….”
Looks like this is a common problem (including on the mac) over the last 6 months and every time someone posts about it, the topic is closed automatically without satisfactory resolution ( 18859,16554, 16234, 15627, 15291).
Uninstalled and Reinstalled the UI and it worked for a day, then after boot up and successful connection today it dropped off in the middle of a session with same symptoms.
15291 recommends using the cli, zerotier-cli join but recieve a 0 join connection failed message.