with htaccess files.

so if someone enter
https://www.domain.com

i want to redirect him to http://www.domain.com

if (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] == 'on') {
your condition here ...
}

;)

Redirect / http://yourdomain.com/

Would probably do it.

Iggy

At present if they type https://www.domain.com where does it go ?

they go https://www.domain.com (https://www.domain.com/)

Are you trying to do this in order to prevent security warnings? If so it won't work - the warnings will be generated when the ssl connection is established, before the redirect can take effect.

But if you still want to try, this should do it:
RewriteCond %{HTTP_HOST} ^www\.domain\.com$
RewriteCond %{SERVER_PORT} ^443$
RewriteRule (.*) http://www.domain.com/$1 [R=301,L]

You can also try the 302 - permanent redirection.
If it is suitable in your case.