apache - force non www to www in htaccess

Question

I have:

# BEGIN WithoutWWW
RewriteEngine On
RewriteCond %{HTTP_HOST} ^mysite.com [NC]
RewriteRule ^(.*)$ http://www.mysite.com/$1 [L,R=301]
# END WithoutWWW

But it won't work. I can still access both www and non www versions. What am I doing wrong?

Answer 1

Try:

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

//OR
RewriteEngine On
RewriteCond %{HTTP_HOST} !^www.
RewriteRule (.*) http://www.%{HTTP_HOST}%{REQUEST_URI} [R=301,L]