Redirect 301 /old-page.html http://www.mydomain.com/new-page.html


RewriteCond %{HTTP_HOST} ^aaa\.com$ [NC]
RewriteRule ^(.*)$ http://www.aaa.com/$1 [R=301,L]

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RewriteCond %{HTTP_HOST} !^www\.
RewriteRule ^(.*)$ http://www.%{HTTP_HOST}/$1 [R=301,L]