I'm at a loss. Partly, if this problem was consistent, it would help, but there's no consistency. At least 90% of the time, when I submit an order and it passes the values to ePDQ, the OID is blank (""). I've tried going through the code; unfortunately, I'm more of a hacker than a coder, so I only partially understand the coding to get and then post the OID in the epdq.php file.
When I go to post, when I'm going to enter the credit card number at ePDQ, I'll look at the source code and notice the OID is blank. So I'll go back and fiddle around with the order and try to resubmit and generally there is no OID. But then once in a while (and I can't find the pattern), the OID is suddenly filled in and the order carries along.
The major issue is, of course, that unless the OID is passed to ePDQ and then returned, the order will not complete; the customer will return to the catalogue with items in his shopping cart, even though the payment has gone through with Barclays.
Anyone have any ideas what is happening or what direction I should be looking?