Case A: In my old installation of ISPConfig 3, I simply set the ISPConfig3 host as example.com. So localhost was example.com In Postfix configuration, I also set mail server as example.com. Then, in file /etc/aliases, I added this line to direct all root messages to myself: root: myself These were not problems as I did everything in one single VPS. So from within ISPConfig3 Control Panel GUI, I could set up a catch-all email box [email protected] which in turn received all system OS mails being sent to [email protected] This is important to system administrator as OS informs root some crucial situations of its system. Case B: Now, I am setting up a new ISPConfig 3.2.5. I plan to expand its potential. This time, I install ISPConfig 3.2.5 on a host defined as isp.example.com. Therefore, localhost becomes isp.example.com. Next, I configure Postfix to have mail server as mail.example.com. In file /etc/aliases, I also add this line: root: myself Now I enter https://isp.example.com:8080/ , register a new domain mydomain.tld and a new catch-all mail box [email protected]. Then, I find that I can no longer receive OS messages being sent to [email protected] as I could in Case A. It is because [email protected] becomes [email protected] and this latter mailbox cannot be defined by ISPConifg 3.2.5. Can you help me to solve my problem? How can I catch all OS messages sent to [email protected] in my new personal mailbox [email protected]?