new post link leads to 404 error page

It’s possible this is a permissions error, relating to a incorrect permissions for a particular fine used in post editing. Have you tried setting correct permissions for your WP install? Here’s a bit of further documentation: https://codex.wordpress.org/Changing_File_Permissions

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