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I own a domain, suppose www.something.com. How can I make a web page with a link like www.abc.something.com ? I want to add something in front of the root domain name. Please help.
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Have you created the subdomain? This is something done at the hosting level. From there, you can do things with .htaccess and rewrites to do "other" things with it, but ultimately you have to create it at the host level.