1062 Duplicate entry - on upgrade

Hi,
I wonder if there iss anyone with the time and patience to help a "newbie" to Zen Cart.
Our site was designed by a firm who basically showed us the admin control panel and left us to it. The site has worked very well for us and has/is generating a substantial amount of business. Unortunately it's too much traffic and we've gone over our allotted bandwith quite substantially. As a consequence of this and of being hacked a number of times we are trying to migrate the site to a dedicated server and perform the 1.37 to 1.38 upgrade.
After much headbanging and a generous amount of help from our new host we had the site running on the new server (as a test site) and decided to peform the upgrade.
Having followed the upgrade instructions and gotten id of all the errors I hit the Database upgrade button, it the tells me that i need a 1,37 to 1,38 upgrade - I hit the button and get the following error message:-
1062 Duplicate entry 'Customers who have never completed a purchase' for key 2
in:
[INSERT INTO query_builder (query_category, query_name, query_description , query_string) VALUES ('email,newsletters', 'Customers who have never completed a purchase', 'For sending newsletter to all customers who registered but have never completed a purchase', 'SELECT DISTINCT c.customers_email_address as customers_email_address, c.customers_lastname as customers_lastname, c.customers_firstname as customers_firstname FROM TABLE_CUSTOMERS c LEFT JOIN TABLE_ORDERS o ON c.customers_id=o.customers_id WHERE o.date_purchased IS NULL');]

Duh???
anyone help someone who is way out of his depth ??ards

Cheers

Chris

You might try using UPDATE instead of INSERT INTO.

the insert into is baked in the update...

you might want to get in your database and delete the Customers who have never completed a purchase entry by hand

All good now except i'm getting the customer return login error.
have created new customer and he logs in and out ok, have made sure that the
tpl_login_default.php
tpl_timeout_default.php
have the additional lines in them but still no luck.
My admin login is fine and the site seems to be selling items as well (to the new customer).

Also,

How do I migrate the current database (v 1.3.7) when i want to go live on the new site v 1.3.8 - is it just a case of backup and restore or will i then end up having a 1.3.7 database on my new site??

Thanks for the advice

Chris