About 15% of the confirmation emails sent in the past 20 days have not been received by the users trying to sign up on my forum. The others receive them just fine.
Why is this happening, any idea?
In the Email Options, the 'email transport method' is default, and the 'set return path' was unchecked. I've checked that now. I can understand there are problems with the email configuration if no emails were being sent, but what's the reason behind it partially working?