Hvad går det galt her? PHP fil upload

HTML kode 

 <form action="process.php?DO=useravatar" method="POST" enctype="multipart/form-data">
     Upload et billede:<br />
     <input type="file" name="file" id="file" /><br />
     <input type="submit" name="submit" value="Gem" />
 </form>

PHP kode 

 echo "Fil: " . $_FILES["file"]["name"] . "<br />";
 
 $rand = rand( 100 , 20000);
 $base = "/home/borgens1/www/";
 $dir = "/uploads/";
 $filename = $_FILES["file"]["name"]."_".$rand."_".$_FILES["file"]["name"];
 
 $file = $base.$dir.$filename;
 
 move_uploaded_file($_FILES["file"]["name"] , $file);
 chmod($file , 0755);