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Hallo Bernd, Of course, I agree with everyone else that you need to fix your robots.txt file. However I'd also add the suggestion that you setup Google Webmaster Tools for your site. These will help inform you about crawl errors and your robots.txt file and might be helpful for you in future. Also whilst having a quick look at your site I noticed some duplicate page title issues. Make sure you are tracking your site with SEOmoz's campaign tool. It will really help you find these types of issues. Viel Glück!