diff --git a/phpBB/includes/emailer.php b/phpBB/includes/emailer.php
index 3e2c64ecd8..72a881f266 100755
--- a/phpBB/includes/emailer.php
+++ b/phpBB/includes/emailer.php
@@ -169,7 +169,7 @@ class emailer
 
 		if ($drop_header != '')
 		{
-			$this->msg = trim(preg_replace('#' . $drop_header . '#s', '', $this->msg));
+			$this->msg = trim(preg_replace('#' . phpbb_preg_quote('#', $drop_header) . '#s', '', $this->msg));
 		}
 
 		return true;