Hi, I searched and saw another member having a similar issue, but it did not mention a resolution. I have setup a course, enabled a payment gateway, and turned on subscriber signups in Wordpress. When I click Enroll while logged out, I get the signup popup just fine - and it does in fact create a Wordpress user account, however after submitting the signup, the popup goes blank. If I dismiss the blank popup, the new user is now logged in, and clicking the Enroll button provides the same blank popup. My guess was that the popup is trying to move to the payment step for the user, and MarketPress is installed and configured, however it's just blank.