I am using PayPal classic API. When I try to reach out for the sandbox test account API credentials, I got the empty screen below. Can anyone tell me what is going on?
Solution
Finally I succeeded ¡¡¡¡¡¡ This works ;)
Log out Paypal account
clearing browser cache and cookies (I use firefox).
Go to developer.paypal.com and login with the real paypal account (not the Sandbox one)
Go to Applications
Click on Sandbox accounts
(Optional) Import your old accounts from your former Sandbox account after the redirect to the accounts page
Create a test account if one doesn't already exist
Click link Enter Sandbox site
Log in to that site using your test business account
Go to Profile -> My Selling Tools -> API Access
Click to Request API Credentials
Choose the option that solves your needs
The API credentials were created !!! (they will appear in your test account profile)