I am running an ecommerce site that was doing well on Google. We switched our shopping cart to magento enterprise and after a couple of weeks Google webmaster reported 15,000 crawl errors. At the same time we saw our rankings drop by 20-30 positions. After a couple of months our error count has grown to 32,623 not found pages. Does anyone know how to deal with such a huge number of errors? Do crawl errors correlate to a drop in rankings? Some of the errors need to have 301 redirects but the majority of them are coming from query pages that the system generates based on product attributes. I recently blocked all query pages in the robots file, but I am not sure if that is the best solution.
Any advice on this topic would be greatly appreciated.