diff --git a/phpBB/includes/acp/acp_styles.php b/phpBB/includes/acp/acp_styles.php
index faa16570c5..d2a0f9210f 100644
--- a/phpBB/includes/acp/acp_styles.php
+++ b/phpBB/includes/acp/acp_styles.php
@@ -643,10 +643,11 @@ parse_css_file = {PARSE_CSS_FILE}
 		{
 			while (($file = readdir($dp)) !== false)
 			{
-				if (!is_dir($file))
+				if (!is_dir($phpbb_root_path . 'styles/' . $file))
 				{
 					continue;
 				}
+
 				$subpath = ($mode != 'style') ? "$mode/" : '';
 				if ($file[0] != '.' && file_exists("{$phpbb_root_path}styles/$file/$subpath$mode.cfg"))
 				{