[jlaine]

Just for further review -

I found if you delete the category from the admin panel, it doesn't apparently remove the reference to it from articles_category table - that seems to be causing articles_categoryid to reference the wrong catid when you go to update.

Mine was showing

Invalid SQL:
UPDATE articles_category
SET categoryorder=
WHERE articles_categoryid=5

But the actual category I was trying to update was 8..

Upon removing the categories that were deleted prior via sqladmin and attempting to update the categories again, script worked fine.