I setup postfix and mailutils, but when I try sending emails it fails.

When I check my mail using “mail” it shows undelivered messages.

When I open any of the email, it gives this error.

<^>This is the mail system at host ubuntu-s-1vcpu-1gb-sgp1-01.

I’m sorry to have to inform you that your message could not be delivered to one or more recipients. It’s attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can delete your own text from the attached returned message.

               The mail system host[] said: 550-5.7.28 [ 1] Our system has detected an unusual rate of 550-5.7.28 unsolicited mail originating from your IP address. To protect our 550-5.7.28 users from spam, mail sent from your IP address has been blocked. 550-5.7.28 Please visit 550-5.7.28 to review our 550 5.7.28 Bulk Email Senders Guidelines. j17si92723pgj.49 - gsmtp (in reply to end of DATA command) <^>

What am I missing? I configured everything from the tutorials is what I believe.

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Hi @utsavrathour,

It seems big providers are stopping mails from your Droplet reaching it’s customers. There are can be a lot of reasons behind this but let’s try with the initial steps. Make sure the domain you are sending messages from to have a DKIM,SPF and DMARC DNS records. This will help authenticate your domain when sending out messages.

Once you do, check a few blacklists if you by accident have been placed on it. You can use your droplet’s IP address to check.

Regards, KFSys