I have a client that has a robots.txt file that is blocking an entire subdomain, entirely by accident. Their original solution, not realizing the robots.txt error, was to submit an xml sitemap to get their pages indexed. I did not think this tactic would work, as the robots.txt would take precedent over the xmls sitemap. But it worked... I have no explanation as to how or why. Does anyone have an answer to this? or any experience with a website that has had a clear Disallow: / for months , that somehow has pages in the index?