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My first question on this community.. A high traffic site of mine has been severely hit for over two months. I took a look at GWTC and noticed a lot of suggestions on the HTML suggestions tab, where I believed that one or a combination of these errors/notices might been causing the penalty. At the moment of typing GWTC shows no HTML suggestions and minor meaningless crawl errors. Checking on SEOMOZ reported issues, I see zero errors except for a high number of duplicate page titles resulting from tag pages being accessible in the same tag title in paginations (tag.html?page=x) which can be fixed easily by using rel=canonical but I just know it can't cause such penalty. For reported warnings, site has a decent amount of title element being too long and missing meta tag description tags. I have been very active in the past with 301 inner pages of the site to make pages URLs as unique as possible and results were great, but that was long time ago before taking the hit. The penalty the site suffers from is zero rankings for newly added contents and old contents as well. It has also lost all rankings for its money terms. Site is not banned and still ranking top for its name which is a good thing. I am not sure where else I should be looking and will appreciate any good advices. Thanks!