You don’t have Handle in excess of the obtaining SMTP server. SMTP servers are listening on port 25 to receive emails. They assume SMTP purchasers to hit port twenty five. There’s no other port for receiving emails. If your Postfix don’t connect with port 25 of your receiving SMTP server, https://stephenbdday.wikibyby.com/775178/5_tips_about_business_email_server_hosting_you_can_use_today