Error setting up external cron

I am checking out the trial before I purchase and want to make sure I can get everything working through plugnpay.

I am using plugin for plugnpay, and when I go to advanced tab and click on box to enable external cron, then save at bottom I get the following error:



Forbidden
You don't have permission to access /amember/admin/setup.php on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.


Update:.... I tried a test transaction through plugnpay and it worked, even without the external cron enabled