Simple Cart
The default cart setup for PayPal only requires the primary email address used at your PayPal account profile setting. If the
Smart Checkout method is used, there must be a
Client ID created. The ID does not exist as a default so it must be done as a process.
Create Client ID
Log into your PayPal account
Go to the developer area at
https://developer.paypal.com/developer/applications
* If an APP already exist, click the name to enter edit mode and get the Client ID
Create a new app to generate the Client ID
- Switch to Live on the top selector
- Click the button labeled Create App to enter the App setup view
- Enter a name in the field labeled App Name to identify if in the list
- Click Create App to save.

Enter a name for the new App

The new App will show the Client ID. Copy the ID.

Paste the copied Client ID into the PayPal Smart Checkout section for Client ID