First thing we can try is replacing the specific configuration key that might be causing the problem. Take a backup of the database then carefully copy and paste the following into Admin->Tools->Install SQL Patches and click Send :
Let me know if that fixes the problem.
DELETE FROM `configuration` where configuration_title='New Products Listing- Number Per Page';
INSERT INTO `configuration` (configuration_title, configuration_key, configuration_value, configuration_description, configuration_group_id, sort_order, date_added) VALUES ('New Products Listing- Number Per Page', 'MAX_DISPLAY_PRODUCTS_NEW', '10', 'Number of new products listed per page', '3', '14', now());