/wp-admin/post.php shows 404 template on submit

The domain didn’t have www. in the wordpress settings. Adding this worked. No idea what the problem was exactly, but this solved it.

Edit: Not yet fixed. It was mod_security which blocked ‘WordPress.com.’ (I’m at Namecheap which uses mod_security)

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)