They can only tell if the client will be compatible with the server or not, because the 'protocol version' is compared when joining a server. They can detect versions and kick people that use the wrong version.
Spoutcraft), they can force vanilla clients. 3 If they can force Spigot clients (e.g.2 They disabled my radar in Rei's minimap!!!.1 They can detect versions and kick people that use the wrong version.
