Title: Error when posting comment
Last modified: August 19, 2016

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# Error when posting comment

 *  Resolved [skynight](https://wordpress.org/support/users/skynight/)
 * (@skynight)
 * [18 years, 6 months ago](https://wordpress.org/support/topic/error-when-posting-comment/)
 * Hi WP,
 * I got this error when i posted comment on my site:
 * > WordPress database error: [Table ‘xxxxx_blog.wp_post2cat’ doesn’t exist]
   >  SELECT
   > cat_ID AS ID, MAX(post_modified) AS last_mod FROM `wp_posts` p LEFT JOIN `wp_post2cat`
   > pc ON p.ID = pc.post_id LEFT JOIN `wp_categories` c ON pc.category_id = c.cat_ID
   > WHERE post_status = ‘publish’ GROUP BY cat_ID
   > Warning: Cannot modify header information – headers already sent by (output
   > started at /home/xxxxx/public_html/wp-includes/wp-db.php:160) in /home/xxxxx/
   > public_html/wp-content/plugins/ajax-comments/ajax-comments.php on line 193
   > Warning: Cannot modify header information – headers already sent by (output
   > started at /home/xxxxx/public_html/wp-includes/wp-db.php:160) in /home/xxxxx/
   > public_html/wp-content/plugins/ajax-comments/ajax-comments.php on line 194
   > Warning: Cannot modify header information – headers already sent by (output
   > started at /home/xxxxx/public_html/wp-includes/wp-db.php:160) in /home/xxxxx/
   > public_html/wp-content/plugins/ajax-comments/ajax-comments.php on line 195
 * Any idea?

Viewing 1 replies (of 1 total)

 *  Moderator [Samuel Wood (Otto)](https://wordpress.org/support/users/otto42/)
 * (@otto42)
 * WordPress.org Admin
 * [18 years, 6 months ago](https://wordpress.org/support/topic/error-when-posting-comment/#post-665956)
 * You are using a plugin or theme that is not compatible with WordPress 2.3, because“
   post2cat” no longer exists. It has been replaced.
 * First post in the support forums:
    [http://wordpress.org/support/topic/135564?replies=88](http://wordpress.org/support/topic/135564?replies=88)

Viewing 1 replies (of 1 total)

The topic ‘Error when posting comment’ is closed to new replies.

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 1 reply
 * 2 participants
 * Last reply from: [Samuel Wood (Otto)](https://wordpress.org/support/users/otto42/)
 * Last activity: [18 years, 6 months ago](https://wordpress.org/support/topic/error-when-posting-comment/#post-665956)
 * Status: resolved

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