Usage of the LDAP service in Kerio MailServer is easy. Simply, the following two conditions must be met:
At least one LDAP service or Secure LDAP must be run in Kerio MailServer.
The user must have his/her contacts defined in the contacts folder or must have subscribed at least one public or shared contact. No contacts will be found unless this condition is met.
Note: If Kerio MailServer is protected by a firewall and the LDAP service is intended to be available, the appropriate ports must be open (389
for the LDAP service and 636
for Secure LDAP). You should use the encrypted LDAP version.