Paypal - This transaction cannot be processed due to invalid

Hi All

This is my first ever post as I've managed to find answers to previous issues, but......

I'm almost ready to put my new Opencart site live (1.5.1.3) and I'm just testing the PayPal Website Payment Pro and I get the message:

"This transaction cannot be processed due to an invalid merchant configuration"

I have read many posts on how to resolve this and no matter what I try I am still getting the same error.

I have a UK Payment Pro account, but as suggested by everyone I am using the PayPal Website Payment Pro extension (not UK) . I have cleared my API 'User', 'Password' and 'Signature' fields and re entered the data numerous times but I still get the same error message. Ihave even requested new API data from Paypal and entered this as suggested by other posters.

Other things I have tried is to clear cookies and history.

Please can someone help as I have been going round and round in circles for hours and need to get this sorted so that I can start earning and paying the dreaded household bills.

Thanks in advance for any help!!

Hi,
I have the same problem, i was wondering if you got any help/answers?

Thanks for your time

Laurent

Did you guys figure this out? I'm having the same issues.