One more link to KB: How to configure a passive ports range for ProFTPd on a server behind a firewall
It is the same as "315 duplicate DKIM Signatures in one Email Header". Submitted as PPPM-5476.
# sudo yum -y install poppler-utils
Did you see KB...
Plesk does not provide Apache. It's installed from OS repos.
CentOS based on RH. RHEL 7: based on upstream v2.4.6 (c)...
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