Index: helpers/file_helper.php
===================================================================
--- helpers/file_helper.php	(revision 15437)
+++ helpers/file_helper.php	(working copy)
@@ -423,7 +423,7 @@
 		 * @param Array $forbidden_names
 		 * @return string
 		 */
-		public function ensureUniqueFilename($path, $name, $forbidden_names = Array())
+		public function ensureUniqueFilename($path, $name, $forbidden_names = Array ())
 		{
 			$parts = pathinfo($name);
 			$ext = '.' . $parts['extension'];
@@ -441,7 +441,7 @@
 			// when storage engine folder is supplied as a part of $name
 			$this->CheckFolder($path);
 
-			do {
+			while (file_exists($path . '/' . $new_name) || in_array($path . '/' . $new_name, $forbidden_names)) {
 				if ( preg_match('/(.*)_([0-9]*)(' . preg_quote($ext, '/') . ')/', $new_name, $regs) ) {
 					$new_name = $regs[1] . '_' . ((int)$regs[2] + 1) . $regs[3];
 				}
@@ -450,8 +450,7 @@
 				}
 
 				$original_checked = true;
-				$res = file_exists($path . '/' . $new_name) || in_array($path . '/' . $new_name, $forbidden_names);
-			} while ($res !== false);
+			}
 
 			if ( $parts['dirname'] != '.' ) {
 				$new_name = $parts['dirname'] . '/' . $new_name;