email sends to spam of gmail account
<p>I have set automatically to send email to users from my website. but this email will place to spam of users with gmail accounts.However it is working fine with yahoo or hotmail accounts. 
How should I solve this? </p>

<pre><code>$to = "$Email";
$subject = "Greeting";
$message = 'message here';
$from = "sender@example.com";
$headers = "MIME-Version: 1.0" . "\r\n";
$headers .= "Content-type:text/html;charset=iso-8859-1" . "\r\n";
$headers .= "From: sender@example.com" . "\r\n" .
  "Reply-To: sender@example.com" . "\r\n";            

                mail($to,$subject,$message,$headers);
</code></pre>
