diff --git a/web/zm_html_view_event.php b/web/zm_html_view_event.php
index 133fe2819..cd8d43748 100644
--- a/web/zm_html_view_event.php
+++ b/web/zm_html_view_event.php
@@ -36,7 +36,7 @@ if ( !$result )
 	die( mysql_error() );
 $event = mysql_fetch_assoc( $result );
 
-if ( !isset($mid) )
+if ( empty($mid) )
 {
 	$mid = 0;
 	$mid_sql = '';