MailChimp single opt-in question

Hello. s2Member pro user.

I’m trying to troubleshoot why new registrants aren’t being added to my MailChimp mailing list.

My question: Once I’ve configured my site for single opt-in by using the mu-plugins/s2-mc-hacks.php filter, on the MailChimp side, should I have double-opt in enabled or disabled?

I have left it disabled on MailChimp, but on the S2member settings, I have "Double Opt-In Checkbox Label set, and checked by default “(Yes, the Box MUST be checked)”. However, new users are not being added to my Mailchimp list.

Looking at the log, I don’t see any errors (reluctant to paste it here as it has user data). No mail merge settings are set in MailChimp. Any ideas?


I couldn’t get it fixed on my own. Essentially in the logs, api_response was returning blank and no e-mail was being sent to the user nor were they being added to the mailing list.

I was, however, able to add users fine through cURL and by creating a custom PHP page with dummy data. It did not work, however, using s2member’s code.

Solution: Deleted MailChimp, now using AWeber