I have set up a "Perfect Server" wit ISPconfig according to the tutorial on a vServer, where I moved 6 Wordpress Websites for 4 clients to. I am not n expert for mail configuration or issues related, so I didn't want to run mail service for the domains, but I want the Websites to send mail from the contact forms - I just can't get that working. I had it going well on the previous server (stretch), but now I can't even send mail from the CLI. Most probably it is a configuration problem, as postfix is running. I also ran the htf-common-issues.php script - the output is attached. Any help will be appreciated.