Did you move your wordpress page to different server/database and now you are unable to login to wordpress admin interface, because you receive “You do not have sufficient rights to access this page“? Did you change table_prefix in wp-config.php file?
The solution is simple – check user usermeta (meta_key) and options (option_name) tables. There are some keys that use table_prefix as part of the key and wordpress is unable to read user rights and roles.
Simple but confusing…