Help please with DNS
I installed the ubuntu web server like in this lesson.
All work well. But when I send emails to some servers like hotmail.com and some other I get this answer:
550-Message rejected. Spamscore threshold (100 points) reached. Spamscore is 550-110! Details: Suspicious e-mail address; Suspected PTR DNS record points 550 to dynamic IP pool; Untrusted domain zone; Suspicious HELO argument; (in reply to RCPT TO command)
My domain is glt.md
Can somebody help me? please what I do incorrectly?