CC部分在php邮件功能中不起作用

I have this php code for mail. Everythings working fine but the CC part is not working

$headers = "From:".$from."
"; 
                $headers.= "Cc: dainest7138@gmail.com
";
                $headers.= "MIME-Version: 1.0
"; 
                $headers.= "Content-Type: text/html; charset=utf-8
"; 
                $headers.= "X-Priority: 1
"; 

                mail($to_mail, $subject2, $mess2, $headers);

Now the mail is being recieved at the address defined in from. The content and all other things are fine but no mail is being recieved on the address defined in "CC" part.

Please Help me understanding the problem.

Thank You

Try this:

            $headers = "MIME-Version: 1.0" . "
";
            $headers .= "Content-type:text/html;charset=UTF-8" . "
";


            $headers .= 'From:'.$from. "
";
            $headers .= 'Cc: dainest7138@gmail.com' . "
";


            mail($to_mail, $subject2, $mess2, $headers);

Re-edited it. Try this one.