When doing the setup of ISPconfig, you will be asked for a host name (like www) when so, do not enter anything.
The next question will be for the domain name (like example.com). When asked, enter the server IP.
Later (when your domain is working), you can change all the needed info within ISPconfig.
Please note that if your server is on a LAN, that you use the LAN IP at the domain name question.
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