I did a `site:www.convertup.com` in Google only to find that 2 copies of all my pages were being indexed. One without a trailing slash which was going into Google’s supplemental index, and one URL with a trailing slash.

You can see the one in the supplemental index hasn’t been crawled in a while because it still has my old title structure.

Luckily someone makes this handy-dandy Wordpress Plugin called Permalink Redirector . It redirects all calls to pages without a slash on the end to the page with the slash. I could have just edited my .htaccess file to do this, but I’ve found out the hard way not to try to “hack” anything if somebody has already done the work for you.

The next time Google goes to crawl the page without the trailing slash, it will be redirected to the one with the trailing slash, and I should see these pages drop from the index since technically they no longer exist.

I’m not sure if this is a new Wordpress 2.1 problem or if previous versions suffered from this problem as well, but you Wordpress users may want to check your sites. Both pages in the index may cause duplicate content issues and lower your ranking, or your PageRank could leak across to the false duplicate pages. Maybe not though, but better just to fix it anyways.