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Need a little help troubleshooting an SEO issue. The day our sitemap finished processing in Google Webmaster Tools, almost all of our keyword serp results tanked. Our top 4 keywords routinely were placing from 11 - 33 rank in serp result and now they're not even on in the top 200?  Would the sitemap processing have anything do do with this or should I look somewhere else. FYI: Site is build in DNN, sitemap is fine and robot.txt file is good. Open to all suggestions!!