I have installed 3CX on a test server and trying to import users from AD but it tells me that 'The entered domain is invalid. Please enter another one and try again'. Our domain ends with .internal but if I put .local or something else I get 'The connection to the LDAP server was refused'. It appears to be a bug to me, can someone from 3CX confirm this. I would like to know if this will be resolved soon.