Unable to log in to the mail account using mail clients (such as Outlook, Thunderbird etc.) after the PCI compliance was enabled:
# plesk sbin pci_compliance_resolver --enable all
Webmail Authentication is working fine.
pci_compliance_resolver utility disables plaintext authentication by performing the following changes in Mail Server configuration:
disable_plaintext_auth = yesfor Dovecot.
Disallows plaintext authentication for non-encrypted connections for Courier.
Verify which Mail server is being used - Dovecot or Courier at Tools & Settings> Mail Server Settings > Installed IMAP/POP3 Server.
Or via the command:
# systemctl | egrep -i "dovecot|courier"
dovecot.service loaded active running Dovecot IMAP/POP3
Disable the PCI compliance:
# plesk sbin pci_compliance_resolver --disable [dovecot|courier]