We have courses where students enroll through email-based self-enrollment and Paypal. We are running Moodle 1.9.19+ but are changing to 2.5.1, where we anticipate the same problem.
We have had hundreds of problems with the confirmation email that is sent out as part of the email self-registration process. Recipient email servers unpredictably block Moodle's automated emails as spam, AOL will not deliver ours at all, GMail sporadically rejects them. We have worked and worked to prevent this, without success. Our email server does not appear on any of the major spamblocker blacklists, but Moodle's automated confirmation emails are, nevertheless, often rejected.
Here's what I think I want to do. Is it feasible? Is it possible? --
I want to to have students sign up using the email based self-registration, fill out a ReCAPTCHA, and go straight to Paypal, without having to respond to a link in a confirmation email first.
The ReCAPTCHA and Paypal should keep spammers from going any further, right? The confirmation email does nothing except confirm the email address of the student enrolling, right?
Am I missing anything? Is this a plausible approach to enrollment for courses like ours that use Paypal? Can it be done?
Is there some other magic we can apply to get our confirmation emails to go through and not be blocked by spam catchers?