Guess this is because 1.17 does all via ldaps - not ldap anymore.
Got an AD too but no certificate management and no ssl support on the server side (which i do not want to change).
hudson.plugins.active_directory.ActiveDirectorySecurityRealm.domainControllers" with the value of the format "host:port,host:port,...". The port should be normally 3269 (for global catalog over SSL), 636 (LDAP over SSL), 3268 (for global catalog), or 389 (LDAP.)
does not work - because ssl is forced, but there is no one on the server side which does speak ssl.
Please make an additional option to switch between non-ssl and ssl - like: