Prevent Zimbra from sending X-Mailer / X-Originating-IP headers

For security reasons you might not want to send email that contains the X-Mailer and X-Originating-IP headers. To disable this follow below steps.

First login to the Zimbra server with SSH.

su zimbra

# Prevent Zimbra from sending X-Mailer header
# Set to FALSE:
zmprov mcf zimbraSmtpSendAddMailer FALSE;

# Get current value:
zmprov gcf zimbraSmtpSendAddMailer;

# Prevent Zimbra from sending X-Originating-IP header
zmprov mcf zimbraSmtpSendAddOriginatingIP FALSE;

# Get current value:
zmprov gcf zimbraSmtpSendAddOriginatingIP;