Paypal Sandbox doesn't work: "We cannot process this transaction..."

[redmoskito]

Hi there,

for several hours I'm trying to test the Paypal sandbox but it doesn't work. I'm using Joomla 1.5.15 and Virtuemart 1.1.4.

After creating a seller and a buyer account at https://developer.paypal.com I put in the Seller Log-in Email (seller_1273763078_biz@...) at the virtuemart admin area. Testmodus is turned off.

Sending a payment to PayPal sandbox returns this message:

We cannot process this transaction because there is a problem with the PayPal email address supplied by the seller. Please contact the seller to resolve the problem. If this payment is for an eBay listing, you can contact the seller via the "Ask Seller a Question" link on the listing page. When you have the correct email address, payment can be made at http://www.paypal.com.

The extra informationen URL is changed, too ->

Code Select Expand

$url = "https://www.sandbox.paypal.com/cgi-bin/webscr";

I don't know, whats's wrong. Does anybody know? I also read Soerens article at http://forum.virtuemart.net/index.php?topic=39584.0 but It doesn't help.

Thanks and bye!

Roland