said: 550-5.7.26 Your email has been blocked because the sender is
   unauthenticated. 550-5.7.26 Gmail requires all senders to authenticate with
   either SPF or DKIM. 550-5.7.26  550-5.7.26  Authentication results:
   550-5.7.26  DKIM = did not pass 550-5.7.26  SPF [turgutdurmaz.com.tr] with
   ip: [2a02:6b8:c02:900:1:45:d181:d102] 550-5.7.26 = did not pass 550-5.7.26
   550-5.7.26  For instructions on setting up authentication, go to 550 5.7.26
   https://support.google.com/mail/answer/81126#authentication
   38308e7fff4ca-2e95bf32d36si22007821fa.580 - gsmtp (in reply to end of DATA
   command)

Merhabalar. @gmail.com uzantılı mail adreslerine mail gönderimiyoruz. This is the mail system at host mail.yandex.net. I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below. You can find the the possible reasons of the undelivered message letter here: https://yandex.com/support/mail-new/wizard/zout_send/not-got-report-yes-other.html Please, do not reply to this message. <tgtd07@gmail.com>: host gmail-smtp-in.l.google.com[2a00:1450:4010:c0b::1b] said: 550-5.7.26 Your email has been blocked because the sender is unauthenticated. 550-5.7.26 Gmail requires all senders to authenticate with either SPF or DKIM. 550-5.7.26 550-5.7.26 Authentication results: 550-5.7.26 DKIM = did not pass 550-5.7.26 SPF [turgutdurmaz.com.tr] with ip: [2a02:6b8:c02:900:1:45:d181:d102] 550-5.7.26 = did not pass 550-5.7.26 550-5.7.26 For instructions on setting up authentication, go to 550 5.7.26 https://support.google.com/mail/answer/81126#authentication 38308e7fff4ca-2e95bf32d36si22007821fa.580 - gsmtp (in reply to end of DATA command) Böyle bir hata vermektedir. başka e posta işletimcilerinde hata vermiyor