Improve the solution for issue #1631

.htaccess directives compatible with both Apache 2.2 and 2.4
diff --git a/system/.htaccess b/system/.htaccess
index ae1d1e6..6c63ed4 100644
--- a/system/.htaccess
+++ b/system/.htaccess
@@ -1,6 +1,6 @@
 <IfModule authz_core_module>
     Require all denied
 </IfModule>
-<IfModule access_compat_module>
+<IfModule !authz_core_module>
     Deny from all
 </IfModule>
\ No newline at end of file