Resolved How to change HELO hostname in POSTFIX?

[Piekielko]

The server domain name in Plesk is the one marked in yellow.
The MX address is mail.piekielko.com.
How to change the name HELO on mail.piekielko.com ?

 

[IgorG]

Look at "smtp_helo_name" option for Postfix config Postfix Configuration Parameters

 

[Piekielko]

Thanks for the tip. it did not give a positive effect but I found "myhostname =" in the main.cf file.
After the change everything works perfectly. I am rated 10/10 at mail-tester.com.