These forums are locked and archived, but all topics have been migrated to the new forum. You can search for this topic on the new forum: Search for Changed a VirtualServer Domain name and the old domain remains active on the web? Is this the way it works? on the new forum.
Well, reachability of a website mainly depends on two things: The domain needs to be resolved to an IP address, and the webserver running on that IP address must serve the right content for the domain.
When you changed your name, the DNS query result for the old name will remain in nameserver caches for a while, so it will still resolve. And if the new Virtualmin domain name happens to be the default for the server, it will be served for the now probably unknown old domain name.
This is how the effect you're seeing might occur.