Hi Martin,
Tim alerted me to this issue. Please make sure that the user that WordPress is using to access your MySQL has permissions to either truncate or "delete from" the table.
You can go ahead and truncate the table yourself using the mysql command" truncate table wp_wfHoover;". DO NOT just delete the file or you'll corrupt your DB. Only do this via mysql.
Then run a scan and let us know if it's completing and what the status is of that table after the scan.
Thanks.