Hello, We have been facing this Issue from long time..But Unable to figure out if this is with Keycloak or OpenLdap.. Could you please help us by understanding the below scenario in Integrating Keycloak with OpenLDAP In user federation we have added an OpenLDAP server with the required details and the "TestConnection" and "Test Authentication" got succeded. But when we tried to sync users we are getting the below Exception: 12:22:21,866 ERROR [org.keycloak.storage.ldap.idm.store.ldap.LDAPOperationManager] (default task-23) Could not query server using DN [o=foo] and filter [(&(ou=External,ou=People,o=foo)(objectclass=posixAccount)(objectclass=top)(objectclass=inetOrgPerson)(objectclass=organizationalPerson)(objectclass=person)(objectclass=shadowAccount))]: javax.naming.OperationNotSupportedException: [LDAP: error code 12 - The server is not configured to pass through control 1.2.840.113556.1.4.319]; remaining name 'o=foo' After searching for above error..we found/suspected (Link:https://kb.informatica.com/solution/21/Pages/136192.aspx) that it is because of some pagination issue with both Keycloak and LDAP provider end.So we disabled the pagination and tried to login directly.But here also we are getting the Error like "User not found". Erro log: 12:34:46,141 WARN [org.keycloak.events] (default task-12) type=LOGIN_ERROR, realmId=Test, clientId=http://10.50.68.44:8080, userId=null, ipAddress=10.125.155.49, error=user_not_found, auth_method=saml, redirect_uri=http://10.50.68.44:8080/plugins/servlet/saml/auth, code_id=6c3359b4-0c36-4b8e-9924-7acbd3439155, username=user1 The User we tried is the same user that was given in the "Bind Credentials" field and the "Test Authentication" was succeded. Please help us what extra information to be configured to achieve this. Please find the attachmnets for the configuration of OpenLDAP with Keyclaok: <http://keycloak-user.88327.x6.nabble.com/file/t585/ldap2.png> <http://keycloak-user.88327.x6.nabble.com/file/t585/ldap1.png> -- Sent from: http://keycloak-user.88327.x6.nabble.com/