Customers get following message on a blank screen after hitting order submit button:

'WARNING: An error occurred. Please refresh the page and try again"

The actual order DOES go thru and I also get the order confirmation email. I am using Paypal payment modules, which handle transactions without any errors.

When I look in to the error logs, I have following errors:


[12-Apr-2016 13:09:41 America/New_York] PHP Warning: Illegal string offset 'cost' in /home/*****/public_html/includes/classes/order.php on line 355

[12-Apr-2016 13:19:58 America/New_York] PHP Fatal error: 1146:Table '******.zen_orders' doesn't exist :: SELECT * FROM zen_orders
WHERE orders_id = 7968
LIMIT 1 in /home/******/public_html/includes/classes/db/mysql/query_factory.php on line 120

[12-Apr-2016 13:20:05 America/New_York] PHP Warning: Creating default object from empty value in /home/*****/public_html/ipn_main_handler.php on line 354
[12-Apr-2016 13:20:05 America/New_York] ERROR: Failed sending email to: " " <> with subject: "Order Confirmation No: 7969" (failed validation)

[12-Apr-2016 13:30:34 America/New_York] PHP Warning: Creating default object from empty value in /home/*****/public_html/includes/modules/shipping_estimator.php on line 92