Gmail rejects emails from our server, says spam, what should I do?

Question

gmail

From our server, when trying to send a letter to gmail, the following response comes:
<******@gmail.com>: host gmail-smtp-in.l.google.com[173.194.222.27]
said: 550-5.7.1 [***.***.228.8 12] Our system has detected that this
message is 550-5.7.1 likely unsolicited mail. To reduce the amount of spam
sent to Gmail, 550-5.7.1 this message has been blocked. Please visit 550
5.7.1 https://support.google.com/mail/answer/188131 for more information.
y8si15720951lfc.226 - gsmtp (in reply to end of DATA command)
Please tell me what to do. I'm not a sysadmin, but I can see the settings if that.

Answer 1

Do you have a link on where to start?

Answer 2

On the freBSD server, I found the library: p5-Mail-DKIM-0.37
I can't figure it out yet, is this enough to create a key and register it in the DNS?
If so, tell me, pliz, what command to do this? Thank you!

Answer 3

Contact support

Answer 4

I have the same problem. I fight for three weeks. Emails are not coming to gmail. Otlup with the same error. Implemented the recommendations. I wrote a letter to them through feedback from the logs.
If I send a letter from my domain via telnet, then I get a whack, but if I add a beleberda ... for example, the sender's address is [email protected], then Google accepts the letter without problems.