[HOWTO] ... setup 'PayPal' correctly with my shop ?

Dear Community.
Dear Admins.

I am really frustrated, as I want to setup Paypal Standard module in my shop and its not working.
Trying this now 1 week.
I did read everything about, and I assume I followed also all instructions.

However, when "testcomer" buys "testproduct" ...
testcustomer: (from Germany)
testproduct: ok, active, with EURO
Germany is not restricted. No country restricted.

... can checkout and going through 'shopping cart'
When it comes to 'payment' a red messege appears:
'No payment methode available'

Here are the settings in my paypal:
. Website Payment Preferences:
AutoReturn: ON
ReturnURL is set
Payment Data Transfer (PDT): ON
ID-Token: (yes given)
Encrypted Website Payments: OFF
Paypal Account Optional: ON

Here are the setting in nopCommerce (under Payment Methods):
only one active is 'PayPal Standard'
support capture: false
refund: false
partial refund: false
void: false
recurring support: NotSupported

and its configured as follows:
use sandbox: disabled
biz email: (my paypal-email)
PDT Token: (very long and correct)
PDT validate order totals:enabled
addl fee: 0.23 € for test
pass productnames: disabled
email IPN: enabled
IPN Handler: (I took the default-mentioned using my store-domain)


Now something I saw today in PayPal under the 'Profile Seller Settings'
is a section called: API settings
here its asked to decide between 2 options:
(A) Grant API permissions to a third party to use certain PayPal APIs on your behalf?
(B) Request API credentials to create your own API username and password?

Do I have to leave that as is, or is there action required?
What exactly?
My shop is hosted at arvixe.

I am not experted, many things doesnt mean anything to me, so I am desperately asking for your help.
I need to get this running soon.

I also have a Prepaid VISA creditcard which is valid until 31 OCT and has 20 USD left.
Would be perfect opportunity to test it 100% with it.

Many Thanks in advance!

Pls anyone can help me ?

Why is nobody helping me ??

https://www.nopcommerce.com/boards/t/19112/v265-one-page-checkout-if-only-one-payment-method-then.aspx


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