Unable to create domain in Plesk with Postfix with Postscreen: mailmng-transport failed: Fatal error: plesk::mail::postfix::PostfixConfigurationError(unable to parse /etc/postfix/master.cf)

Symptoms

• The following configuration for Postscreen can be found in /etc/postfix/master.cf:

  # cat /etc/postfix/master.cf
  smtp inet n - y - - smtpd
  smtp inet n - n - 1 postscreen
  smtpd pass - - n - - smtpd
  dnsblog unix - - n - 0 dnsblog
  tlsproxy unix - - n - 0 tlsproxy

• Postfix version is 3.1.0.

• When creating a domain in Plesk, the following error appears:

  PLESK_ERROR: Error: mailmng-transport failed: Fatal error: plesk::mail::postfix::PostfixConfigurationError(unable to parse /etc/postfix/master.cf)

• The following error can be found in /var/log/plesk/panel.log:

  CONFIG_TEXT: [2019-01-14 18:43:26.433] ERR [util_exec] proc_close() failed ['/opt/psa/admin/bin/mailmng-transport' '--add-domain-to-sender-transport' '--domain-name=example.com' '--ip4-addr=203.0.113.2' '--transport-type=domain-ip'] with exit code [1]
  [2019-01-14 18:43:26.433] ERR [1] PleskUtilException: '/opt/psa/admin/bin/mailmng-transport' '--add-domain-to-sender-transport' '--domain-name=example.com' '--ip4-addr=203.0.113.2' '--transport-type=domain-ip' failed with code 1.
  stdout:
  Fatal error: plesk::mail::postfix::PostfixConfigurationError(unable to parse /etc/postfix/master.cf)
  stderr:
  Fatal error: plesk::mail::postfix::PostfixConfigurationError(unable to parse /etc/postfix/master.cf)

Cause

Resolution

Workaround

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