@till, do you mean in "Email" -> "Global Filters" -> "Content Filter"? I didn't know. Thank you.
In order to avoid the loop issue you have to enable in /etc/postfix/main.cf the following statement. header_checks =...
What is your PHP version? This should be related to php-5.6. All encrypted client streams now enable peer verification by default. If you use a...
[In theory, theory and practice are the same. In practice, they are not.]
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