When trying to make a paypal donation to support ABP I receive the following error:
Access Denied
You don't have permission to access "http://www.paypal.com/cgi-bin/webscr" on this server.
Reference #18.662e2017.1639720591.4490ae54
A brief bit of research leads me to Github https://github.com/openhood/paypal/commit/master
I am just assuming here of course but a brief read through some code lead me to believe that you may need to update the ABP code to work with latest paypal updates. Just a thought, you may want to look into as it is my understanding that I am looking at a PHP,server error response from paypal rather than a webpage response. I can't imagine paypal servers being down.