i can't login to admin site !!!!

Hi All,
Please can anybody help me on this, I have an website WordPress 2.8.6 (www.mydomin.com) and everything is working just perfect and database Prefix (wp_), the Permalink been activated (/%category%/%postname%/) and the plug-in WP Super Cache installed.
Now my problem is I did copied the website wordpress core files from (www.mydomin.com) to a new folder to (www.mydomin.com/es/) also I copied the database and to new Prefix (wp_es_), in database I changed both values siteURL and HomeURL in wp_es_option from (www.mydomain.com) to (www.mydomain.com/es) also I deleted the .htaccess from the (www.mydomain.com/es) root, but when I tried to login to admin site am getting (You do not have sufficient privileges to access this page ), I did tried to change the password, or adding AUTH_KEY and others nothing worked !!! anyone can help me out !!!

thanks in advance …