Wp_Mail and Contact Form 7

try this one

add_filter('wp_mail_from', 'doEmailFilter');
add_filter('wp_mail_from_name', 'doEmailNameFilter');

function doEmailFilter($email_address){
    if($email_address === "[email protected]")
        return '[email protected]';
    else
        return $email_address;
}
function doEmailNameFilter($email_from){
    if($email_from === "WordPress")
        return 'MySite.com';
    else
        return $email_from;
}

This checks if WP is going to send mail as a system (as wordpress@something) and if so, changes to your setting. Otherwise, is using inputs data (mail and name).