I'm having a problem that others have had in the past, but the exchanges of messages are six months to two years old and don't appear to relate to WP 3.2.1 administered on a Mac (and hosted by Go Daddy).
I successfully installed and activated the plugin, and all the fields look fine. However, when I have tried to send emails to my site from another computer (also a Mac) I always get the message "Failed to send your message. Please try later or contact the administrator by another method" in a red box and preceded by something spinning, maybe an arrow. Can someone tell me what's going on?