diff --git a/src/interfaces/handler.php b/src/interfaces/handler.php
index fe1dc1a..5dc8fff 100644
--- a/src/interfaces/handler.php
+++ b/src/interfaces/handler.php
@@ -136,7 +136,7 @@ public function __isset( $name )
      */
     protected function checkFileName( $file )
     {
-        if ( strpos( $file, "'" ) !== false || strpos( $file, "'" ) !== false || strpos( $file, '$' ) !== false )
+        if ( strpos( $file, "'" ) !== false || strpos( $file, '"' ) !== false || strpos( $file, '$' ) !== false )
         {
             throw new ezcImageFileNameInvalidException( $file );
         }