Help for Aimeos

I have a problem with PaypalExpress payment.
Everything goes perfect till the final when paypal site opens with url https://www.paypal.com/webscr&cmd=_exp (this is set in paypalexpress.PaypalUrl)
then it forwards to Error page , not appearing Login screen of Paypal
Did anyone come across the problem? Thanks

I use the parameter &C=EUR following the recommendations here
Re: problem with second price of the products

Could this be the problem?

The URL for PayPal isn't generated by the TYPO3 UriBuilder so that shouldn't be a problem.
What error message is shown?

I have included with images what happens




There is no error in the log of Aimeos. Second image shows empty page and reloads the error page

The "paypalexpress.PaypalUrl" is There are parameters missing in yours.

thank you. That were the problem
you have written "There are parameters missing in yours."
Are there other parameter missing?

Don't think so.