If your site answers on both www.example.com and example.com without redirecting one to the other, search engines can crawl and index every page twice, and an audit reports many issues twice over.
Why Joomla sites get it
Web servers usually serve both names by default, and Joomla answers on whichever one was requested. It is easy to miss because your browser remembers the version you normally use.
Fix it by hand
- Choose one host, with or without
www.. - Redirect the other to it with a permanent (301) redirect. On Apache or LiteSpeed hosting that is a rewrite rule in
.htaccess, and some hosting control panels have a redirect setting for it. - Use the same host in the System – SEF plugin’s Site Domain and in your site URL, so canonical links and other absolute URLs agree.
A typical .htaccess rule sending the bare domain to www. (replace example.com with your own domain):
RewriteCond %{HTTP_HOST} ^example\.com$ [NC]
RewriteRule ^(.*)$ https://www.example.com/$1 [R=301,L]Fix it with MetaGen
MetaGen’s Canonical host agreement check shows which host your pages name, warns when the Site Domain and site URL disagree, and warns when the other host still answers instead of redirecting.
MetaGen is free for Joomla 5 and 6. See all the SEO warnings MetaGen checks.
