peter i am really sorry but i think you don`t know what you are write, the fact is, we can under Plesk tools activated the mailinglist, after that must be worked, when not here is a problem from site Plesk not from user from the panel.
And I'm really excited here because none of the plesk team here is responds to the thread, I am sure that it is not user-specific error here must necessarily look the plesk team the problem.
And that what you say is not correct i have tested different domains with SSL and without SSL and have change hosting setting to cgi to apache and settings have tested to but always same error, and you talk always from ssl and A record and so, i think CNAME is here correct setting that is setted from plesk!
Therefore, I do not find it right that you write the whole time any suggestions here of which you do not know from the topic, thereby you are doing me only unnecessarily much work, and that is not ok