title: Why double line breaks \n\n doesnt work in attachment mail?
body: <p>Im having problems with line breaks when sending mail with php. The main issue here is, that the line breaks doesnt work in mails with attachment (multipart/mixed) but in plain text they do.</p>
  
  <pre><code>&lt;?php
  function sendMail($email, $name, $pdfpath) {
          // $file should include path and filename
          $filename = basename($pdfpath);
          $file_size = filesize($pdfpath);
          $content = chunk_split(base64_encode(file_get_contents($pdfpath))); 
          $uid = md5(uniqid(time()));
          $subject = "New attachment mail: ".$name;
          $subject = "=?UTF-8?B?".base64_encode($subject)."?=";
          $body = "Hello Dude!\n\n"
               ."Testing\n\n"
               ."Testing\n\n\n\n"
               ."Testing\r\n"
               ."Testing\n";
          //combine two headers (attachment mails needs to have specific headers)
          $header .= $this-&gt;attachment_headers;
          $header .= "Content-Type: multipart/mixed; boundary=\"".$uid."\"\r\n\r\n";
          $header .= "This is a multi-part message in MIME format.\r\n";
          $header .= "--".$uid."\r\n";
          $header .= "Content-type:text/plain; charset=UTF-8\r\n";
          $header .= "Content-Transfer-Encoding: 8bit\r\n\r\n";
          $header .= $body."\r\n\r\n";
          $header .= "--".$uid."\r\n";
          $header .= "Content-Type: application/octet-stream; name=\"".$filename."\"\r\n"; // use different content types here
          $header .= "Content-Transfer-Encoding: base64\r\n";
          $header .= "Content-Disposition: attachment; filename=\"".$filename."\"\r\n\r\n";
          $header .= $content."\r\n\r\n";
          $header .= "--".$uid."--"; 
  
          //( string $to , string $subject , string $message [, string $additional_headers [, string $additional_parameters ]] )
          return mail($email, $subject, "", $header);
      }
  ?&gt;
  </code></pre>
  
  <p>So, the output with this in my email is following:</p>
  
  <pre><code>Hello Dude!
  Testing
  Testing
  Testing
  Testing
  </code></pre>
  
  <p>So, it does add a new line, but only one, I need to have more. How can I do that?</p>