I have this problem that new users can't register themselves on my website (blog). I have downloaded and installed all the new versions and I use the Cimy plugin for e-mail. I can send test e-mail from within wordpress without any problems.
When a new user try to register he/she will get the error message "Message failed to send to email@example.com from" and no e-mails has been sent. Also the user is not created in the wp_users table, but is created in the wp_signups. However, if I add the user from within wordpress everything seems to go OK and e-mails are sent. Can anybody help me with this problem ?