Google Webmaster Tools: How To Fix Bad Site Links
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In Google Webmaster tools, you can see which links Google is seeing as bad or broken links. You just go into your reports and take a look for which links are resulting in errors. You can then either block access to those pages through your .htaccess file, or you can simply fix the links which are sowing as bad or giving errors.
Learn how to do (almost) anything:
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