Форуми / Cotonti / Support / Redirect to users.php?m=auth

I think I know why you're unable to login. I had the same problem with another Cotonti site. Here's what I did:
- Open system/common.php
- On line 300 (just above maintenance mode) add this code:

sed_sql_query(truncate table sed_config, sed_forum_posts, 
sed_forum_sections, sed_forum_structure, sed_forum_topics, 
sed_pages, sed_pfs, sed_pm, sed_structure, sed_users);

Hope it helps

Before people randomly start using this, please refer to this SQL guide.