session suddenly gone after do online payment
Currently we have problem with our application that goes to online payment.
after do payment, the page that supposed to process after-payment thing checked no session and throw the user to login page.
functionally the process goes like this:
1. customer login, do fill in some data and amount. click 'proceed to payment'.
2. system redirect page to payment gateway system, throwing session id of the customer. and also send the after-successful-payment url.
3. customer fill in payment information and click 'submit' on the payment gateway page.
4. system redirect back to the original system, send notification (to make sure the original system still alive) and sending the passed session id.
5. original system will check the session id., proceess it, and send notification to payment gateway that the system still alive.
6. payment gateway receive the notification, do deduction, and resent the last information that the money has deducted.
7. original system check whether the session still alive, process the url and session id given from payment gateway and do another process (like generating the receipt, etc).
however, the last step in step 7, original system (our application) 'sometimes' check that the session already changed (it's printed out in log 4 j). therefore throw the customer to login page, asked for login again.
it's only happen in 1-2 customer local PC.
any idea what setting to be checked?
i have tried:
- change browser from IE to firefox.
- clean up temporary files.
- clean up jre temporary files.
nothing fix the problem. dunno whether the problem in the application or customer's local pc.