[SOLVED] Paypal : redirect error

Hello

j3.4.1
cb2.0.9
cbsubnightly from 21/05/2015

I have setup paypal gateway and a paypal sandbox
user registers, comes to the paypal site, logs in, pays an sees the screen where paypal says :

...
Votre paiement d'un montant de €10,00 EUR a été effectué.
Vous allez maintenant être redirigé vers test facilitator's Test Store.

So it is supposed to come back to my site.

What i get is a screen saying : INVALID
(the url is something like : http://mysite/index.php/cb-registration/pluginclass?plugin=cbpaidsubscriptions&cbpgacctno=1&cbppdtback=xxx&cbpbasket=4&result=success&cbpid=yyy

I have setup on the sandbox vendor account :
"Renvoi automatique" activated
I put in my sites URL : kind of mysite.fr/

Perhaps I have to put in a more specific URL ?
Or do I have to setup cbsub for this return URL ?

On the sandbox the payment is registered,
but in CB Paid Subscriptions: Subscriptions the status of this user is "Registered Unpaid"

Please help !

Please review your CBSubs documentation carefully and configure as instructed. Please also follow the backend gateway parameter instructions when configuring the PayPal gateway. Note the sandbox can be a bit wonky. They provide multiple test credit cards designed to simulate scenarios. For example some of them will, on purpose, cause a failed purchase or an error to test how your system handles it. Review CBSubs > Notifications and CBSubs > History carefully for any errors or further information; typically the notification it self (whether PDT or IPN) will include why it failed or why CBSubs rejected it.

I already used the sandbox accounts for another project and I think they should work

I again went through paypal gateway configuration in cb doc 7.4.1 and I think its ok - here the principal setups I made :
Enable single payment
PayPal Sandbox server
PayPal Account and PDT Identity token (required) : mail & token

Here is the log information you told me to look at.

IPNs don't look to be configured. That's a PDT, which looks correct. I recommend creating new sandbox credentials (generate a new business account) for your new site as you maybe missing a parameter somewhere. The fee also maybe causing you issue. Turn the fee off at PayPal and see if that allows it to come through.

The "IPN notification not authenticating at payment gateway" notification type is logged when there's an invalid response from PayPal API (means the payment info is invalid or a fraud attempt due to mismatch). There should be more details in CBSubs > History regarding the API call and its response.

Ok I checked my paypal preferences :
I had not IPN enabled which is done now (I had to enter an URL so I put in the url of my site - if this needs to be more specific let me know)
And PDT setup was not complete which is done now

Now after paypal I come back to the site which is fine but I get this error message :

Désolé, mais votre paiement n'a pu être traité. Résultat de la transaction:FAIL Error: 4020. Veuillez retenter et informer les administrateurs du site.
Aucun panier appropriée trouvé.

In the payment notifactions I get :

Notification type PDT notification not authenticating at payment gateway

and this raw data :

Raw result FAIL
Raw data $_GET=array (
'plugin' => 'cbpaidsubscriptions',
'cbpgacctno' => '1',
'cbppdtback' => 'xxx',
'cbpbasket' => '7',
'result' => 'success',
'cbpid' => 'xxx',
'tx' => 'xxx',
'st' => 'Completed',
'amt' => '10.00',
'cc' => 'EUR',
'cm' => '7',
'item_number' => 'S17-549-2',
'option' => 'com_comprofiler',
'view' => 'registers',
'Itemid' => '113',
'task' => 'registers',
);
$_POST=array (
);
$transaction_info='FAIL
Error: 4020';
$PDT_RESULT=array (
0 => 'Error: 4020',
);

I read some other posts related, checked all the Ids but can't find anything wrong (in my eyes)

Ensure you're using a test credit card number that's designed for a successful response. PayPal provides multiple test cad numbers with different test responses. Some will fail payment on purpose.