Quote Originally Posted by njcyx View Post
Hi @lat9, I gathered some information for the recent duplicated orders after OPC is installed:

Example 1:
Paypaldp
fedexwebservices

Order placed time:
06/23/2022 11:37:35
06/23/2022 11:37:36
06/23/2022 11:37:37

These orders are not marked as guest-checkout
Domestic shipping address

Example 2:
Paypaldp
fedexwebservices

Order placed time:
06/22/2022 19:59:29
06/22/2022 19:59:30

These orders are not marked as guest-checkout
International shipping address

Example 3:
Paypaldp
fedexwebservices

Order placed time:
06/02/2022 17:27:30
06/02/2022 17:27:31
06/02/2022 17:27:31

These orders are marked as guest-checkout
Domestic shipping address

So it looks like the duplicated order only occurs when the customer is paid by credit card (paypaldp) and selected FedEx shipping method (which takes a little bit longer time to load than USPS).

Do you think increasing AJAX timeout time will help? Currently it is set to 5s by default.
Increasing that AJAX timeout might help, but without understanding the underlying cause of the duplicates, it's a patch at best. Where did you find that fedexwebservices shipping method?