diff --git a/redirector.php b/redirector.php
index 74383d4..ca42f04 100644
--- a/redirector.php
+++ b/redirector.php
@@ -69,7 +69,7 @@
     # echo 'SUBTAG:' . $_SUBTAG . ' TAG:' . $_TAG . '<br>';
     
     # strip potentially bad characters from file
-    $_SUBTAG = preg_replace('/["\'?%$#@!;*&]/i', '', $_SUBTAG);
+    if ($_SUBTAG != "") $_SUBTAG = preg_replace('/["\'?%$#@!;*&]/i', '', $_SUBTAG);
 	$_TAG = preg_replace('/["\'?%$#@!;*&]/i', '', $_TAG);