diff --git a/lib/fileproxy/quota.php b/lib/fileproxy/quota.php
index f770c9cb32..94a49176ee 100644
--- a/lib/fileproxy/quota.php
+++ b/lib/fileproxy/quota.php
@@ -27,8 +27,10 @@
 
 class OC_FileProxy_Quota extends OC_FileProxy{
 	private function getFreeSpace(){
-		$usedSpace=OC_Filesystem::filesize('');
+		$rootInfo=OC_FileCache::get('');
+		$usedSpace=$rootInfo['size'];
 		$totalSpace=OC_Preferences::getValue(OC_User::getUser(),'files','quota',0);
+		$totalSpace=OC_Helper::computerFileSize($totalSpace);
 		if($totalSpace==0){
 			return 0;
 		}
diff --git a/settings/ajax/setquota.php b/settings/ajax/setquota.php
index 5c07285cfc..d4e3c58ac1 100644
--- a/settings/ajax/setquota.php
+++ b/settings/ajax/setquota.php
@@ -6,10 +6,13 @@ require_once('../../lib/base.php');
 OC_JSON::checkAdminUser();
 
 $username = $_POST["username"];
+
+//make sure the quota is in the expected format
 $quota= OC_Helper::computerFileSize($_POST["quota"]);
+$quota=OC_Helper::humanFileSize($quota);
 
 // Return Success story
 OC_Preferences::setValue($username,'files','quota',$quota);
-OC_JSON::success(array("data" => array( "username" => $username ,'quota'=>OC_Helper::humanFileSize($quota))));
+OC_JSON::success(array("data" => array( "username" => $username ,'quota'=>$quota)));
 
 ?>
diff --git a/settings/users.php b/settings/users.php
index 686c4b6a9b..e5dcc04948 100644
--- a/settings/users.php
+++ b/settings/users.php
@@ -18,7 +18,7 @@ $users = array();
 $groups = array();
 
 foreach( OC_User::getUsers() as $i ){
-	$users[] = array( "name" => $i, "groups" => join( ", ", OC_Group::getUserGroups( $i ) ),'quota'=>OC_Helper::humanFileSize(OC_Preferences::getValue($i,'files','quota',0)));
+	$users[] = array( "name" => $i, "groups" => join( ", ", OC_Group::getUserGroups( $i ) ),'quota'=>OC_Preferences::getValue($i,'files','quota',0));
 }
 
 foreach( OC_Group::getGroups() as $i ){