Linux – Unable to send email using Postfix

Below outlines the issue and resoultion when trying to send email using Postfix.


When trying to send an email on my linux platform I get the following error message in my mail.log ??

The IP you’re using to send mail is not authorized 550-5.7.1 to send email directly to our servers.      Please use the SMTP 550-5.7.1 relay at your service provider instead. Learn more at 550 5.7.1 u14si20903226gvf.6 (in reply to end of DATA command))


This is down google thinking that you could poss be a spammer.

1. Add the following line to your /etc/postfix/ file,

relayhost = <ISP Relay Server Name>

      Change the server name to your ISP relays server name.

2. Restart postfix – ‘/etc/init.d/postfix restart’

Rick Donato

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