In the General Guidelines for Google Webmaster Tools, Google advises that there are steps you can take to proactively address duplicate content issues and avoid receiving a duplicate content penalty. One such step is:
- Use Webmaster Tools to tell us how you prefer your site to be indexed: You can tell Google your preferred domain (for example, http://www.example.com or http://example.com).
I recently set this up for my Abipo domain name and I had the choice of either:
- Display URLs as www.abipo.com
- Display URLs as abipo.com
As I have always preferred the www prefix, I chose the former: “Display URLs as www.abipo.com” . However, upon choosing this option, I received an error:
Part of the process of setting a preferred domain is to verify that you own http://abipo.com. Please verify http://abipo.com.
As I had already uploaded a Google generated HTML file to the root directory of my Abipo web server I was thinking my sites WERE verified. I wondered why Google was asking to verify when it has already been done. Did I need to reverify?
The answer was I needed to verify the http://abipo.com domain AS WELL as the http://www.abipo.com domain name. This was done by visiting the Home Page of Google Webmaster Tools and clicking on “Add a site….”. After I did that, I was able to go back and specify http://www.abipo.com as my preferred domain for indexing.