[Done v1.3.9e] 1.3.9d duplicate orders

[justin2010]

zip file uploaded and messege sent to you via PM, thank you again.

[justin2010]

Dear Doctor,

I know you may already went to bed as it's midnight there. While waiting for your reply, I switched the store to showcase instead of switching back to IPN, hoping it can be solved easily with your help, then I don't have to switch back again. If you need to register a user in my store to test, please let me know.

Thank you very much!


Justin

[DrByte]

Rather than turning off ordering capability, I'd recommend leaving it open to purchases ... and if IPN normally works fine short of an occasional duplicate order, I think that'd be your best approach for now. I'm somewhat doubtful that the PayPal logs will show anything conclusive. More important would be your server's error log records showing the cause of the 500 error.

[DrByte]

The logs show that the DoExpressCheckoutPayment transaction attempts are being submitted twice, which suggests that you're clicking the submit button on the order-confirmation screen multiple times, or refreshing the page after it's already been submitted. The first is going through and being approved, and the second is being rejected because it was already completed and it's preventing you from submitting a duplicate.

I'm puzzled about why you're experiencing the time delays that are tempting you to do the multiple clicking or page refreshing.

[justin2010]

I did NOT click more than once. I am very sure about this.

[DrByte]

Sorry, I'm not trying to be accusational.
Merely stating that the logs show multiple attempts of the exact same data ... and that has to be initiated by the customer's browser. Maybe it was just a page-refresh attempt when it appeared to be frozen? And on two separate occasions.

Again, very puzzled about the cause of the timeout. Everything else looks to be functioning normally, in fact very well.

[justin2010]

Because I used IPN before, so when I switched to express checkout, should I change something in PayPal?

for instance, in IPN, I need to do this,
"in Website Payments Preferences set your Automatic Return URL to:
https://MYSTORE.COM/store/index.php?...eckout_process "

But I noticed in express checkout, I don't have to do it. Does it mean I should go to PayPal and turn it off?

I am not sure about how these work but just feel kind of desperate to fix it, so please don't laugh on my opinions.

[justin2010]

Sorry, I'm not trying to be accusational.
Merely stating that the logs show multiple attempts of the exact same data ... and that has to be initiated by the customer's browser. Maybe it was just a page-refresh attempt when it appeared to be frozen? And on two separate occasions.

Again, very puzzled about the cause of the timeout. Everything else looks to be functioning normally, in fact very well.

I never think you tried to accuse me anything instead I know you are trying to help even thought it's midnight for you. I very appreciate your help.

But truly, I didn't click more than once on the button, and I didn't click on the refresh button of the browser. I was testing, and I was very patient to wait for the result.

But your finding reminds me those customer who got duplicated orders. Perhaps they didn't click more than once either. But I really don't know what's wrong.

[justin2010]

The time delay was strange. In fact, when I tested it, every time I clicked the "Pay Now" button, I received those notification emails from PayPal within seconds. But then the browser froze. Then minutes later, it show the error messege.

It's your midnight. If you want to leave please feel free to do so. Just let me know so I won't wait. Thank you.

[DrByte]

Because I used IPN before, so when I switched to express checkout, should I change something in PayPal?

for instance, in IPN, I need to do this,
"in Website Payments Preferences set your Automatic Return URL to:
https://MYSTORE.COM/store/index.php?...eckout_process "

But I noticed in express checkout, I don't have to do it. Does it mean I should go to PayPal and turn it off?

I am not sure about how these work but just feel kind of desperate to fix it, so please don't laugh on my opinions.

Even using Express Checkout you still want to leave the Website Payment Preferences option for IPN Notification enabled and with the URL pointing to your site's ipn_main_handler.php. That way your store will still receive the IPN notices applicable to order updates such as refunds, etc. (Using Express Checkout just makes your store not have to rely on receiving IPNs to activate orders in your store, and that's good since IPN timing is unreliable at best.)

As for Automatic Return URL, that can be left alone, or removed, if you're not using Website Payments Standard/IPN module. If you're doing eBay or something you'd likely want it pointed to your eBay store, for example.

In both cases, Zen Cart doesn't care what those values are set TO, just that they're set to something valid and enabled ... whether using IPN/WPS or Express Checkout.