Hi, AFAIK openSUSE does not tun its own SMTP server, so if one wants to send a mail he has to use a different (ono-oS) SMTP server. This leads to issues, as one smaller mail provider uses means of sender authentification (see below) in between. How can we deal with these authentifications when using a o.o address? Thanks Axel -- host gmail-smtp-in.l.google.com [66.102.1.26] SMTP error from remote mail server after pipelined end of data: 550-5.7.26 This message does not pass authentication checks (SPF and DKIM both 550-5.7.26 do not pass). SPF check for [opensuse.org] does not pass with ip: 550-5.7.26 [178.254.4.101].To best protect our users from spam, the message has 550-5.7.26 been blocked. Please visit 550-5.7.26 https://support.google.com/mail/answer/81126#authentication for more 550 5.7.26 information. p11-20020a05600c204b00b003b4b2707425si9307880wmg.75 - gsmtp