UAW Plugin

I installed unique article wizard plugin . and when i click on “update ant test” button i got an error massage in red color

“Sorry, there was a problem submitting the test article for dir_id 70167 to http://seoarticles.buy-back-links.com/wp-content/plugins/unique_articles/add_article.php: Error message: HTTP code: 500 for http://seoarticles.buy-back-links.com/wp-content/plugins/unique_articles/add_article.php. Once that page is working, then submissions should work. You may need to contact your hosting company if it is a server configuration error.”