i've got this error :

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We are sorry for the inconvenience. The PayPal account authentication settings are not yet set up, or the API security information is incorrect. We are unable to complete your transaction. Please notify the store owner so they can correct this problem. (10002) 10002 Authentication/Authorization Failed - You do not have permissions to make this API call

can anyone tell me why?
and can anyone tell me how to solve this?
Thanks.
regards.

Hi:

If I have correctly understood you have to go to paypal. Go to Profile
Under "my Account" go to API access.
Choose to get Api credential (signature) you will get a Username, Password and a signature. All of that have to be copied on your Express Checkout Payment Module (Zen Cart)

Copy and paste the api credentials on your Express Checkout payment module.
You have to edit this one. (Configuration--->Payment Modules--->Express Checkout.

I am not an expert. But hope this will help you.
Marlake