You can remove all comments by a single user in WordPress.
- Log into phpMyAdmin (cPanel / Plesk / Web Hosting / Managed WordPress).
- Select the database for your WordPress site in the left-hand column.
- Click the SQL tab.
- Enter the following command into the "Run SQL query..." box:
DELETE from wp_comments WHERE comment_author_email = 'email address'
Update the command for your situation as follows:
- email address is email address associated with the comments you want to remove
Warning: If your WordPress database uses custom table prefixes, then you must replace wp_ in each command with the prefix listed in your wp-config.php file.
- Click Go.
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