The requested domain name is not configured for any web site: http://news.greenmountainpower.com/press-releases/gmp-announces-first-of-its-kind-solar-project-to-i-1137231?feed=d51ec270-a483-4f6c-a55e-8e5fbe2238c2
If you're an administrator of this site, you need to go to Site Manager -> Sites and use the following domain name either in the Site properties or add a new domain alias: news.greenmountainpower.com