Hello to all, after a long struggle I can now proof that Outlook 2013/2016 running within a samba4 Domain , version samba 4.3.4, will now work perfectly with an IMAP Account and Dovecot/Courier Servers. Great thanks to the samba team Daniel EDV Daniel Müller Leitung EDV Tropenklinik Paul-Lechler-Krankenhaus Paul-Lechler-Str. 24 72076 Tübingen Tel.: 07071/206-463, Fax: 07071/206-499 eMail: mueller at tropenklinik.de Internet: www.tropenklinik.de