Why did I get the error "The seller accepts encrypted website payments only" during checkout?

Issue

When using the Donate Button, my customers get this error: "The seller accepts encrypted website payments only. You cannot pay the seller through unencrypted buttons. Please contact your seller for more details."

Cause

Your Paypal account is set up to only accept encrypted buttons. You will need to change this setting in Paypal for our Donate Button to function correctly. 

It's easy to fix:

1. Log in to your PayPal account.
2. Select Profile > Profile and settings.
3. Click My selling tools.
4. Click Update next to Website preferences.
5. Select Off under Encrypted Website Payments.
6. Click Save.