/*Step 1 replace menu-% with your menu name*/

SELECT *
FROM `menu_links`
WHERE menu_name LIKE 'menu-%'
AND module <> 'menu'; 

/*Step 2 - replace mlid number with number of your item*/

UPDATE menu_links set module = 'menu' WHERE mlid LIKE '4078';

Used the first sql statement to find your menu item. (Replace menu-% with the name of your menu eg. "primary-links" .

Then using the menu item id fix the items you want to regain the good old delete button on the menu item.

Drupal 6 - Fix Menu links you can\'t delete by reseting them to delete via SQL

sql, links, drupal

SQL