Ordered redirecting to previous order and not current order

Hello all. I currently have a site and it is hosted on dreamhost. I upgraded via their web panel to Version 1.39d. I do not have any addons installed.

A customer today alerted me that she was redirected to a previous order rather than the other just made. I also tested on a test acct. Both the customer, and I, using PayPal.

I am not sure how how long it has been like this, so it could have been also going on prior to upgrading, or after, thus it may not even be related.

What can I do to check? And what files would contain the redirecting code?

The site is at:
c r o c h e t g a r d e n .com

That happens when you're using the PayPal IPN module which relies on waiting for PayPal's server to tell your server that an order has been placed. It's a common problem, subject to the whims of many factors which could break that communication.
If you switch to Express Checkout instead you won't have that problem.

Or, you'll just have to troubleshoot the communications problems until you've resolved it: http://www.zen-cart.com/wiki/index.php/PayPal

Thank you - I will see about changing. I will keep you posted if I have any other questions. Thank you!