Receiving Paypal IPN response multiple times

Question

I am Using paypal payment gateway IPN in my application for payment.

When payment is done successfully I am receiving IPN response correctly.

After receiving I am sending back it for verification.

$ch = curl_init();

$paypalUrl = PAYPAL_URL;
curl_setopt($ch, CURLOPT_URL, $paypalUrl); 
curl_setopt($ch, CURLOPT_POST, 1); 
curl_setopt($ch, CURLOPT_POSTFIELDS, $post_field); 
curl_setopt($ch, CURLOPT_HEADER, 0); 
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);  
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
$res = curl_exec($ch);

Now I am receiving same IPN response multiple times (exactly about 9 times). I am sending IPN response for varification in following format:

    cmd=_notify-validate&orderUUID=eac962fe-3a0a-4b26-be89-e5ccf54ee2cb&
    mc_gross=15.00&settle_amount=11.58&
     protection_eligibility=Ineligible&payer_id=LR3LZ8R978ZK8&tax=0.00
    &payment_date=06%3A55%3A17+Jun+05%2C+2013+PDT&payment_status=Completed
  &charset=windows1252&first_name=abc&option_selection1=&option_selection2=&
 mc_fee=0.74&exchange_rate=0.812061&notify_version=3.7
  &settle_currency=USD&custom=&payer_status=verified&business=business%40mydomain.com
  &quantity=1&verify_sign=AFcWxV21C7fd0v3bYYYRCpSSRl31AlU7JAwS8--HoB6lJfimizlVxnVa&payer_email=personal%40mydomain.com&option_name1=tour&option_name2=abc+abc&txn_id=6RU07240YB682730C&payment_type=instant&last_name=abc&receiver_email=business%40mydomain.com&payment_fee=&receiver_id=LW9JSM57BYH5Q&txn_type=web_accept&item_name=ite  m+name&mc_currency=AUD&item_number=&residence_country=US&test_ipn=1&handling_amount=0.00 &transaction_subject=item+reserva!tion+for+1+spaces+on+Jun+06&payment_gross=&shipping=0.00&ipn_track_id=b85bc954da9e5

What is the reason for receiving same response multiple times?

As I was following that, we need to send 200 OK to paypal for the IPN response, if Paypal doesn't get the 200 OK it retries again... Is it the same?

Answer 1

Here I experienced one thing. suppose my original hostname is abc.com and I have created one testing instance on that. now my new hostname will be testing.abc.com . when I was doing transaction from my testing instance above problem is occurring(receiving IPN response multiple times). I handled response correctly (i.e checked is this duplicate response or new responce ). Now my application is moved on production environment and my hostname is abc.com and everything is working fine !! (receiving IPN response only once). I Think paypal was not able to receive success status from my testing instancE because of that it was trying to send same response multiple times.

Answer 2

If you check your IPN history in your PayPal account, does it show a status code of 200 being sent back? Typically this is common reason for seeing IPN's multiple times.