> we are struggling with t-online.de: Why don't you post the corresponding maillog entry?
T-online's smtp error messages are quite elaborate and usually contain an email address that you can contact in case of problems. > As you may know as SMTP client you have to fulfill a bunch of requirements Where did you get that information from? According to their documentation they don't even evaluate DKIM or SPF. https://postmaster.t-online.de/index.en.html > to be able to send mails to t-online.de. > From time to time we receive mails from t-online.de, but can't answer. That is probably because your mailserver's ip reputation has not been reset by t-online. Have you ever contacted t...@rx.t-online.de? If not I suggest you try that and ask to unlock your mailserver's ip. It seems your operating commercially, so do not forget to attach a valid imprint to your email, otherwise they will deny your request. Best regards, Gerald _______________________________________________ Postfix-users mailing list -- postfix-users@postfix.org To unsubscribe send an email to postfix-users-le...@postfix.org
