[PHP]Wysylanie naglowka header() Opcje

[webmaestro]

[PHP] pobierz, plaintext 
<?
$filePath ="a/";
$fileName="a.zip";
  $fd = fopen($filePath.$fileName,"r");
  $size = filesize($filePath.$fileName);
  $contents = fread($fd, filesize($filePath.$fileName));
 
  fclose($fd);
 
  header("Content-Type: application/octet-stream");
  header("Content-Length: $size;");
  header("Content-Disposition: attachment; filename=$fileName");
 
  echo $contents;
?>
[PHP] pobierz, plaintext 

Mam taki kod. Nie wysyła mi nagłowek wagi pliku, co zle zrobilem??