Working on a CLONE of an existing site with a view to creating a "duplicate" webshop. Version 1.5.5d (cloned, not fresh install) Both dbase and folders/files copied. configure.php "edited" to reflect new server location, etc.

Now we want to DELETE the customers and orders from the database of this "clone", as these records will not be relevant when the cloned site is ready for going live.

So we access the the customer "list" in admin panel. Select a customer, then DELETE button. (Get asked if we wish to confirm), we then confirm... then white-screen with error.

Looking in LOG files we see:

Code:
[07-Jan-2017 16:25:22 Europe/London] Request URI: /OUR-ADMIN-FOLDER/customers.php?page=1&action=deleteconfirm, IP address: 000.000.000.000
#1  trigger_error() called at [/home/CLONE-SITE/public_html/includes/classes/db/mysql/query_factory.php:167]
#2  queryFactory->show_error() called at [/home/CLONE-SITE/public_html/includes/classes/db/mysql/query_factory.php:139]
#3  queryFactory->set_error() called at [/home/CLONE-SITE/public_html/includes/classes/db/mysql/query_factory.php:266]
#4  queryFactory->Execute() called at [/home/CLONE-SITE/public_html/twiSt-CJT-brAwn/customers.php:404]

[07-Jan-2017 16:25:22 Europe/London] PHP Fatal error:  1064:You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1 :: delete from products_notifications where customers_id =  ==> (as called by) /home/CLONE-SITE/public_html/OUR-ADMIN-FOLDER/customers.php on line 404 <== in /home/CLONE-SITE/public_html/includes/classes/db/mysql/query_factory.php on line 167
Have uploaded new files (customers.php AND query_factory.php) to respective locations, and looked at Dbase table for product_notifications. All appears to be OK... but error persists.