I have people registering who are not getting confirmation emails. (I do get the administration email announcing a new registrant.) I read a few previous posts, and I don't believe it is a WP email problem. Also, they have checked their spam folders as well, but no email ever arrived. Please advise.
wpForo queues all email to Wordpress script. Doesn't send any emails out. Definitely not a wpForo issue.
Install some smtp plugin with extended logging and check what happens.
Like this one for example: