Paypal PDT error 4003

Question

After many hours of messing about and trying to set up what should be the relatively simple process of sending a payment to www.sandbox.paypal.com and being redirected back to a page on my site with a transaction id in the querystring, I have finally achieved it.

I am now receiving an error message 'FAIL Error 4003'.

Here is the code I am using. It is pretty much the same as the paypal example (all I have done is echo out the responses):

    <?php
// read the post from PayPal system and add 'cmd'
$req = 'cmd=_notify-synch';

$tx_token = $_GET['tx'];

$auth_token = "ZdoN6q4GLiRniR2BbOzEEF22GJOWHpVOXRtP7fAhBpvwwm5GyWcTzO_sSSO";
$req .= "&tx=$tx_token&at=$auth_token";

// post back to PayPal system to validate
$header .= "POST /cgi-bin/webscr HTTP/1.0\r\n";
$header .= "Content-Type: application/x-www-form-urlencoded\r\n";
$header .= "Content-Length: " . strlen($req) . "\r\n\r\n";
$fp = fsockopen ('www.paypal.com', 80, $errno, $errstr, 30);
// If possible, securely post back to paypal using HTTPS
// Your PHP server will need to be SSL enabled
// $fp = fsockopen ('ssl://www.paypal.com', 443, $errno, $errstr, 30);

if (!$fp) 
{
    // HTTP ERROR
    echo "HTTP Error";
} 
else 
{
    fputs ($fp, $header . $req);
    // read the body data 
    $res = '';
    $headerdone = false;
    while (!feof($fp)) 
    {
        $line = fgets ($fp, 1024);
        if (strcmp($line, "\r\n") == 0) {
            // read the header
            $headerdone = true;
        }
        else if ($headerdone)
        {
            // header has been read. now read the contents
            $res .= $line;
            echo $line;
        }
    }

        // parse the data
        $lines = explode("\n", $res);
        $keyarray = array();
        if (strcmp ($lines[0], "SUCCESS") == 0) 
        {
            for ($i=1; $i<count($lines);$i++)
            {
                list($key,$val) = explode("=", $lines[$i]);
                $keyarray[urldecode($key)] = urldecode($val);
            }
            // check the payment_status is Completed
            // check that txn_id has not been previously processed
            // check that receiver_email is your Primary PayPal email
            // check that payment_amount/payment_currency are correct
            // process payment
            $firstname = $keyarray['first_name'];
            $lastname = $keyarray['last_name'];
            $itemname = $keyarray['item_name'];
            $amount = $keyarray['payment_gross'];

            echo ("<p><h3>Thank you for your purchase!</h3></p>");
            echo ("<b>Payment Details</b><br>\n");
            echo ("<li>Name: $firstname $lastname</li>\n");
            echo ("<li>Item: $itemname</li>\n");
            echo ("<li>Amount: $amount</li>\n");
            echo ("");
        }
        else if (strcmp ($lines[0], "FAIL") == 0) {
            echo "Failure: " . $lines[0];
            // log for manual investigation
        }

}

fclose ($fp);

?>
<br />
Thank you for your payment. Your transaction has been completed, and a receipt for your purchase has been emailed to you. You may log into your account at <a href="http://www.sandbox.paypal.com/ie">www.sandbox.paypal.com/ie</a> to view details of this transaction.

I have made sure to confirm the email addresses for both my sandbox merchant and buyer accounts and enabled PDT.

The client is redirected correctly back to my 'thank you' page with the following querystring paramaters - ?tx=4FU63684496248523&st=Pending&amt=29.90&cc=EUR&cm=&item_number=

Has anyone else encountered this error message? If so, what are the usual causes?

Answer 1

The problem was that I was sending my test http request to paypal.com rather than sandbox.paypal.com. The answer was in the FAQ left by Jukebox.

Check the script.When testing Payment Data Transfer (PDT) in the Sandbox, make sure your PDT script POSTs back information to www.sandbox.paypal.com. If testing on the Live PayPal site, make sure the script POSTs data back to www.paypal.com. Currently, all sample code on the Live and Sandbox sites "point" back to the live PayPal site.

Hope it helps someone else get up and running quicker than I did. I am now onto my next issue which is the token being returned as empty rather than an error.. sigh..