PayPal PDT is not Returning a tx value in the Query String - paypal

Question

I've gone through the (not so helpful) PayPal docs and can't find an easy answer to this problem. When the user returns from PayPal, the URL does not contain a query string and thus I do not receive the 'tx' value (or any other value for that matter).
This is an example of what I'm sending to PayPal:
<form accept-charset="utf-8" action="https://www.sandbox.paypal.com/au/cgi-bin/webscr" id="paypal-form" method="post">
<input type="hidden" name="business" value="dallas_bus#dallasjclark.com">
<input type="hidden" name="cancel_return" value="http://localhost/checkout">
<input type="hidden" name="cmd" value="_xclick">
<input type="hidden" name="charset" value="utf-8">
<input type="hidden" name="currency_code" value="AUD">
<input type="hidden" name="custom" value="155">
<input type="hidden" name="lc" value="AU">
<input type="hidden" name="notify_url" value="http://localhost/paypal-ipn">
<input type="hidden" name="return" value="http://localhost/checkout">
<input type="hidden" name="item_name" value="ABC Company - Order #155">
<input type="hidden" name="item_number" value="155">
<input type="hidden" name="amount" value="8.95">
<input type="hidden" name="discount_amount" value="0.00">
<input type="hidden" name="shipping" value="25.00">
<input type="image" src="https://www.paypal.com/en_AU/i/btn/btn_buynowCC_LG.gif" name="submit" alt="Buy Now">
</form>
Thanks in advance !

Answer 1

You should check the settings at https://www.sandbox.paypal.com/us/cgi-bin/webscr?cmd=_profile-website-payments and make sure
Auto Return is set to ON
You have specified a Return URL
Payment Data Transfer is set to ON
There's another much less obvious thing I had to learn through experimentation: your form must not contain a "return" value, otherwise that will override the Return URL in your settings and prevent the Auto Return from working and you'll wind up without the necessary tx parameter. This is a relatively recent development (bug?) at Paypal, because it used to work.

Answer 2

I've just been struggling with this for some time, and another thing that seemingly causes no tx value to be returned is if you have a free trial.
So, if the cost of your service is free for the first 20 days then 4.99 thereafter you won't get a tx value back for the first free payment. If you charge one penny (or whatever your relevant currency is) for the initial 'free' period then you will get a tx value returned.

Answer 3

We actually logged a ticket with PayPal Merchant Technical Services to get to the bottom of this.
We found that over time, some paypal merchant accounts would appear to forget their AutoReturn/PDT settings.
Even though you could go into the Website Preferences and AutoReturn and PDT were both enabled; the account would behave as if they were not enabled.
Follow this procedure to reset the settings ....
Click on Profile.
Click on "My Selling Preferences">
Click on "Website Preferences"
(*) Direct link to this section, in case you can't found it -> https://www.paypal.com/cgi-bin/customerprofileweb?cmd=_profile-website-payments
Disable both Auto Return and Payment Data Transfer.
Save your changes.
Access to Website Preferences again.
Enable Auto Return and Payment Data Transfer again.
Save your changes.

Answer 4

I've got the same problem with sandbox during testing. To fix it I had to verify test accounts in sandbox environment. To verify them use the build-in testing e-mail service. After verifying, paypal sandbox started to sent TX parameter.

Answer 5

A few other reasons why you might not get a tx parameter:
For PDT to work, you must confirm the email address used as the value of business in your button code. If this email address is not confirmed, PDT will not work. If your email address is not confirmed, you will not see the PDT query string appended to your return URL.
When you enable PDT, the URL you are using as the default Auto Return URL must be a valid hostname or IP address or the user will not be auto-returned back to that URL. Make sure you use a valid URL as the URL of where you want the user to go back to or you will not see the intended result.
From: https://ppmts.custhelp.com/app/answers/detail/a_id/469

Answer 6

i have found a method, that worked for me - try to insert this field into your generated form code:
<input type='hidden' name='rm' value='2'>
rm means return method;
2 means post with variables
Than after the user purchases and returns to your site url, then that url gets the POST parameters as well
p.s. if using php, try to insert var_dump($_POST); in your return url(script), then make a test purchase, and when you return back to your site you will see what variables are got on your url.

Answer 7

I had a similar problem - where working from a local server,
i used to get instead of the 'tx' variable, i got a 'auth' variable.
After playing around with it for a while, found that (for some wired reason) if i change my vitrual host and host file, to the real domain, i get the 'tx' variable, where as in my local environment domain i get the 'auth' variable.
That fixed it for me.
Hope this helps anyone.

Answer 8

I also opened a PayPal Merchant Technical Services ticket for this.
For transactions initiated by a PayPal Button. The PayPal back end sometimes loses the monetary values of the pricing structure (even though it shows you, and you can edit the pricing, the back-backend will lose the values and not accept updates).
Symptoms: In Sandbox, the PayPal process will fail after login but before it can show you the screen for choosing the funding source (i.e. which back account or credit card to use). You get the "We're sorry; Things are not working" message.
Create the Button anew and hopefully the pricing is saved this time.