PHP file upload issues/file permissions -

having script issues file upload (and/or) file permissions on local xampp server - reports error on file upload. again, user folder created upon successful registration script (note, registration script, user not logged in after registration):

if(mysql_query("insert users(username,email,password) values('$uname','$email','$upass')")) {   ?>      <script>alert('successfully registered');</script>  <?php  $_server['query_string']; $foldername = $_post['uname']; $path = "users/"; $complete = $path.$foldername;  if (mkdir($complete, 0777)) {   ?>      <script>alert('folder <?php echo "\"$foldername\""; ?> has been created';</script>   <?php }   else {    ?>      <script>alert(folder not created);</script>    <?php }                } 

and part of script file upload when user logged in:

    session_start();  $userfolder = $_server["document_root"]."/users/".$_session['user']; $filename = $_files['filep']['name']; $filedir = $userfolder.'/'.$filename;  echo "$filedir".'<br />'.'<br />';  //echo getcwd();      if ($_post['action'] == "load") {          if (file_exists($filedir)) {             ?>                 <script>alert('file" <?php echo $_files['filep']['name'] . "already exists."; ?>');</script>             <?php         }             elseif (!is_writable($filedir)) {                 die ("not writable !");             }                 elseif (move_uploaded_file($_files['filep']['tmp_name'], $filedir)) {                                 ?>                                     <script>alert('file "<?php echo "$filename"; ?> "loaded');</script>  }   

im using local xampp installation c:/xampp/... , echoed $filedir reports c:/xampp/htdocs/users/testuser/, file path should ok, im still getting error ´is_writable´ , ´move_uploaded_file functions´. maybe worth mention $_session['user'] in file path populated in file script:

        if (isset($_post['btn-login'])) {         $email = mysql_real_escape_string($_post['email']);         $upass = mysql_real_escape_string($_post['pass']);         $sql = mysql_query("select * users email='".$email."'");         $num = mysql_fetch_assoc($sql);              if ($num['password'] == $upass) {                 $_session['user'] = $num['username'];                 header ("location: home.php");             } 

any hints ? thank you