WORDPRESS DATA BASE ERROR …

WordPress database error: [Got error 28 from table handler]
SELECT DISTINCT * FROM wp_posts WHERE 1=1 AND post_date_gmt <= ‘2006-03-24 18:07:59’ AND (post_status = “publish”) AND post_status != “attachment” GROUP BY wp_posts.ID ORDER BY post_date DESC LIMIT 0, 10 <———————- i am getting that message. 30 minutes before this, it was working real fine. and i didn’t change anything… i dont know whats wrong. i am a newbie with WP… can anyone tell me whats wrong?

it also happens when i try to MANAGE MY POSTS in WP Dashboard