In order to make Virtualmin work you will most likely need to fix this error. A problem was found with your Postfix Virtual Maps : No map sources were found in Postfix config. Just add the following text in Postfix Webmin > Servers > Postfix Mail Server > Virtual Domains > Domain mapping lookup tables = hash:/etc/postfix/virtual Once the line is added to Postfix, you should go back to Virtualmin module and re-check config. via JazzyMarketing