Question:
hello, I am sending emails with php mail () function from my UPU (Centos 7)
but I have a problem, letters end up in spam, or they don't reach at all (on mail.ru, for example), just postfix, tell me how you can solve this problem? Thank you
Answer:
Check your server IP address if it is blacklisted (for example via https://mxtoolbox.com ). Mail.ru has a stricter filtering system, so it is possible that letters are simply rejected there because of a suspicious address.
Also, to improve the throughput of letters, configure DKIM, SPF and DMARC correctly. You can see what exactly Mail.ru thinks about your server through their service https://postmaster.mail.ru