Dear Till, How are u? I was setup fresh perfect server and using email feature. When sending email to any gmail address message not sending. Please see this undelivered error message host gmail-smtp-in.l.google.com[74.125.24.27] said: 550-5.7.26 This message does not have authentication information or fails to 550-5.7.26 pass authentication checks. To best protect our users from spam, the 550-5.7.26 message has been blocked. Please visit 550-5.7.26 https://support.google.com/mail/answer/81126#authentication for more 550 5.7.26 information. n66si37255584pfd.186 - gsmtp (in reply to end of DATA command) Please help me to solve this issue. Thanks
There are more people on this forum than just Till They refer to this page in the error message: https://support.google.com/mail/answer/81126#authentication On that page, you can read the sender guidelines. You should have a SPF, DKIM, and DMARC record. Your mailserver needs a reverse DNS record for the IP aswell, with the hostname of the mail server.
