Nethserver 7.6.1810 and external domain controller

NethServer Version: 7.6.1810
Module: account provider

Hi all,

we’ve a Nethserver installation which should connect to an external domain controller, based on
Samba 4.7.6 on Ubuntu 18.04. The domain is working properly, with some PCs already connected.
When we try to add on of the domain controller in the Accounts provider page, with all the settings,
it seems to work. The command “id someuser” report the correct data. If we “su - someuser”, the
server create the home directory under /var/lib/nethserver/home, with the correct owner.
The ldap bind, even with “administrator@domain.lan” works in the second step.
But every other application, dovecot, roundcube, webtop, does not recognize the users…
Any idea?

Also under “Users and groups” the web page show an error “Account provider generic error: SSSD exit code 1”

The command “ldapsearch -x -H ldap:// -Z -b “dc=ad,dc=domain” -D administrator@ad.domain -w mysecretpass -s sub” works flawlessly…