A duplicate content HORROR story and warning!

Well, to me at least the last approx. two weeks has been a horror search engine and traffic wise.

The story begins last year when I switched software from UBB.threads to vBulletin+vBSEO. I imported all posts from UBB.threads to vBulletin, but kept the old ubb.threads forum as a read-only "archive" in order not to lose all backlinks, some of which were highly valuable.

To begin wih this worked fine, google began crawling the new site but the old URLs (which would pop up in many search results kept working). I added a 301 redirect from the forum home, but left everything else as is. I did not worry about duplicate content since everything seemeed to work just fine.

Jump ahead to the beginning of January 2007 and the google update. Suddenly one day, about two weeks ago, my traffic from google was down 80-90%!! And since google traffic accounts for the mjority of visitors this was hurtful to say the least. New regsitrations fell from 5-6 a day to 1, if I was lucky.

What could it be?! My site was still indexed in google. The Webmaster's tools did not mention any problems. But it had almost disappeared from the SERPs. And I'm not just talking about a drop from page 1 to page 2 - no, completely gone! For example, for a while my Classical Music Forum has been on page1 when searching for "classical music forum", and the same for other of my forums. But it had gone. Down at #300 the search would show the main forum page, but not the classical music forum. And this went on for 2 weeks - butchering my traffic.

The day before yesterday I decided that it had gone on for too long, and guessed it must have something to do with the old ubbthreads forum still running, so it was time to turn to drastic measures. I closed the entire ubb.threads forum from the public, with the exception of one thread which has been linked from so many places that I cannot afford losing it. Next I put 301 redirects in the apache config file for all forums (post-lists) - something I should have done from the beginning but had problems doing at the time and then forgot about.

This was the day before yesterday, and lo and behold - today I'm back in the SERPs! (crossing fingers it will continue ). Coincidence? I think not...

So, let this be a warning not to underestimate the penalty of duplicate content. It could seem like google since the last update is hitting harder on it. Of course this "evidence" is only anecdotical but I have a strong feeling it's true.

Good information. You should be able to put a custom 301 in place for your "golden thread" too, to redirect it to the imported version of that thread in your vBulletin installation. What are the URLs to the old thread and the new thread?

Thanks Keith. Well, this*** is my "golden thread" (most unfortunately it dropped from PR4 to PR3 a week ago* :() and the new one is: Bach: Toccata & Fugue in D-minor BWV 565 (free) MP3 Download - Magle International Music Forums

Hmmm.. could be time has come to switch it over, but from my experience 301 redirects are not perfect, and it would be impossible for me to get the hundreds of backlinks to the thread changed to the new destination.

(* and now some astute readers may deduct that the PR drop on some of my pages has something to do with the drop in SERPs I mentioned in the OP. However, though the PR drop may account for some lower rankings, the SERP drop I experienced was on a much different scale)

*** UPDATE: I have finally decided to redirect the old ubb threads thread to the new forum. Crossing fingers I can avoid a major drop in SERPs