I recently had some deep pages from another website drop off of Google’s ranks I believe it was from a duplicate content issue. This is still under investigation but what I found was there were two forms of the same page indexed in Google, one with 1 trailing forward slash and another with 2 trailing slashes.
I found this out be doing a site: search for the web pages that dropped in rank.
Duplicate Content Example (this is an example of what showed up):
site.com/page/here/
site.com/page/here//
I was able to fix this by placing the below code into my .htaccess file.
It redirects double slash versions to the single slash version.
RewriteCond %{REQUEST_URI} ^(.*)//(.*)$
RewriteRule . %1/%2 [R=301,L]
SEO Repair: Quick Update: 4-16-11
After revisiting this post I just wanted to note that the duplicate page versions
are no longer listed in Google and the original pages now rank where they did originally.
