The statuscodes flow of an iDeal transaction:
1)
Once the transaction is created in our system, which happens when the customer arrives at the first iDeal screen, the status will be "OPEN". (No postback is sent at this time)
2)
The payment is made by the customer.
3)
After completing the payment (pressing "voltooien" or "return to the webshop" button in iDeal) we will request payment information from the bank and send the proper postback: "OK" if the amount has been paid, "ERR" if it wasn't.
Special case A:
If the customer does not press the "Voltooien" after they pay (i.e. they close the window) we don't know wether the customer has completed the transaction. We will wait for 20~ minutes after the transaction has been initiated to do our first information request to the bank.
Special case B:
If the bank is still processing the data or the iDeal server is not available at the time we request the payment data,
we send an "OPEN" postback (unless an "OPEN" postback has already been sent).