I recently helped a website owner because their website would not appear in Google’s index. I did a site search, you know site:www.example.com with no result.
Of course I first thought the site had been that banned by Google and removed from the index; however, being banned seemed odd. The site was just a couple of months old and getting banned in such a short amount of time did not seem likely.
The SEO aha moment!
I use the SeoMoz toolbar quite a bit, it’s a a great browser plugin that will display various SEO information.
Looking at the page attributes I noticed something odd, the site had the canonical link element on every page set to their Google plus page. No wonder why Google only listed their G+ page, and not any pages from their website!
Matt Cutts from Google talks about canonical urls in a video, and there many ways you can mess up this useful tag. Google will try to figure it out if you get the canonical URL wrong (if they can!).
In this case I guess Google wasn’t smart enough. What can we learn from this? Don’t use the canonical tag if you’re not sure how to use it!