Index: temp/trunk/html/admin/system/bkup.php
===================================================================
--- temp/trunk/html/admin/system/bkup.php	(revision 5793)
+++ temp/trunk/html/admin/system/bkup.php	(revision 5794)
@@ -192,5 +192,7 @@
 		$fp = fopen($csv_file,"w");
 		if($fp) {
-			$err = fwrite($fp, $csv_data);
+			if($csv_data != ""){
+				$err = fwrite($fp, $csv_data);
+			}
 			fclose($fp);
 		}