WordPress Database Error Access Denied

Hi all,

Can anyone help me? My blog is bringing up a blank page or 500 internal error.

Here is what the last log said:

[05-Jun-2011 22:04:49] WordPress database error Access denied for user ‘yscr_bbz7mf’@’localhost’ to database ‘blog1’ for query ALTER TABLE wp_comments ADD COLUMN comment_subscribe_optin_mailed enum(‘Y’,’N’) NOT NULL default ‘N’ made by require_once, require, require_once, do_action, call_user_func_array, __lambda_func, sg_subscribe_start, sg_subscribe->sg_subscribe, sg_subscribe->db_upgrade_check

Does anyone know what this means? I use Yahoo as a host, and started having this problem shortly after I upgraded. I’ve deactivated all the plugins already, and my blog is on the default theme.

Thanks for your help!