if (isSet($letter['tmp_name'])&&(strcmp($letter['tmp_name'],'')!=0)) {


  //find the letter file.  store it as $letteroriginal. $letterbackup is temporary location
   $letterfmt = FindFormat($config['uploadDir'], $idPaper, "l");
   $letteroriginal = "./".FNameLetter ($config['uploadDir'], $idPaper, $letterfmt);
   $letterbackup = "./" . $config['uploadDir'] . "backup1";


   // if the original exists move it to the backup.
   if(file_exists($letteroriginal){
        rename($letteroriginal, $letterbackup);
        $letterbackedup = TRUE;
   }

   if (StoreLetter ($id, $letter, $format, $db)) {

     // if the letter store sucessfully - and there was a backup - delete it
     if($letterbackedup) {
        unlink($letterbackup);
      }
   }
   else {

     // if the letter was backed up and the file didn't upload succesfully - revert it
     if($letterbackedup) {
     rename($backup, $original);
     }
     // return with error
     return "Unable to store the letter <br>";
   }
}