buzztone on "[Plugin: Contact Form 7] CF7 says message sent, but no email sent."

I think the issue may be related to having WP Mail SMTP plugin, however I never remember getting that, or even needing it.

Alternatively you can try to configure email using SMTP. WordPress also supports SMTP mail (another type of mail service) but this needs to be configured separately via the admin area of WordPress - see http://www.callum-macdonald.com/code/wp-mail-smtp/