How to disable various headers in Zimbra
1. To start with, we will first create a custom header check file, that will contain our headers that we want to ignore: $ touch /opt/zimbra/conf/custom_header_checks 2. Once the file is created, we are going to add it to the zimbra configuration: $ zmprov mcf zimbraMtaHeaderChecks 'pcre:/opt/zimbra/conf/postfix_header_checks pcre:/opt/zimbra/conf/custom_header_checks' $ zmprov mcf zimbraMtaBlockedExtensionWarnRecipient FALSE Confirm the new header check file is picked up by zimbra: $ postconf | grep header_checks 3. The next step would be to populate the file with data. Below is an example of this file with various headers: /X-Virus-Scanned/ IGNORE /^Received: from 127.0.0.1/ IGNORE /^X-Originating-IP:/ IGNORE /^X-Mailer:/ IGNORE /^Mime-Version:/ IGNORE /^User-Agent:/ IGNORE /^X-Sanitizer:/ IGNORE /^X-Spam-Status:/ IGNORE /^X-Spam...