I’m using WP 2.8.4, and have my domain/hosting both through GoDaddy. I installed the plugin through the Admin panel and simply followed the directions. I have sent 4 test emails through my contact page ( http://rememberourforefathers.com/index.php/contact-rof-com/ ); I populated the Your Email* field once with my gmail address, once with my ymail address, once with my optonline address, and once with an outlook address hosted by my employer. The former two emails encountered the error message surrounded by the red box (Failed to send your message. Please try later or contact administrator by other way.) The latter two emails went through successfully and were received by my domain address as expected.
Thank you for your help and patience.