Please note that many Sellers experienced configuration problems with PayPal Website Payments Pro ("WPP"), and some reported a high percentage of declined transactions and other problems that were beyond our control. We therefore removed support for WPP, but it's still in place for merchants who started using it earlier.

In order to configure PayPal Website Payments Pro for use with Chargify, you will need to provide Chargify with your API Username, API Password, and Signature.

If you have not enabled API Access on your PayPal account, you may do this by logging in to your PayPal account and doing the following:

• In the "My Account" tab, click on the "Profile" submenu
• Under the "Account Information" section, follow the "API Access" link
• Follow the link for "Request API Credendtials" (under Option 2)
• Select "Request API signature" (not "Request API certificate") and click "Agree and Submit"

Important Notes & Error Conditions

• On the Chargify gateway configuration screen, where we request your API Username and API Password, you will need to provide us with the Username and Password specific to your API Access - this is not the same as the username and password you use to log in to PayPal
• Chargify sites in test mode will only work with the API credentials for a PayPal developer's sandbox account (not a live PayPal gateway account)
• Chargify sites in production mode will only work with the API credentials for a PayPal live account (not a developer's sandbox account)

LESSONS FROM OTHER CHARGIFY MERCHANTS

1. The error mesage "Security Header is Invalid" indicates a mismatch between Live/Test in Chargify and Live/Sandbox in PayPal. If it's REALLY not that problem, then you need to contact PayPal and complain. Usually, things start working again within 24 hours, even though they will tell you that nothing was wrong on their end.

2. The error message "Credit Card is Invalid" can be very misleading. We get this message when the real problem is that we have used the wrong API credentials or we have a mismatch between Chargify and PayPal Live/Test modes.

--- Lance