We tried to give a heads-up in a couple places. The Toolbar beta 5 announcement on the Google blog mentioned “You’ll get suggestions instead of error pages: If you mistype a URL or a page is down, now the Toolbar will give you that familiar “Did you mean” with alternatives, like when you do a Google search.” And the John Mueller did an excellent run-down for webmasters when he talked about the Google toolbar beta on Google’s official webmaster blog. Here’s the part of John’s post that probably interests you:
404 errors with default error pages
When a visitor tries to reach your content with an invalid URL and your server returns a short, default error message (less than 512 bytes), the Toolbar will suggest an alternate URL to the visitor. If this is a general problem in your website, you will see these URLs also listed in the crawl errors section of your Webmaster Tools account.
If you choose to set up a custom error page, make sure it returns result code 404. The content of the 404 page can help your visitors to understand that they tried to reach a missing page and provides suggestions regarding how to find the content they were looking for. When a site displays a custom error page the Toolbar will no longer provide suggestions for that site. You can check the behavior of the Toolbar by visiting an invalid URL on your site with the Google Toolbar installed.
So if you’re a webmaster and want users to see your custom 404 page, just make your page be more than 512 bytes long. I do think that this feature is really handy for most users. Let me give some screenshots to demonstrate what it looks like.
I installed the Toolbar Beta 5 for Internet Explorer and surfed to a 404 page on mattcutts.com, and I see this:
My 404 page, while not that useful, is more than 512 bytes long, so the toolbar doesn’t change the page.
I had to look around a little bit to find a default 404 page. My former grad school has one, so surfing to a 404 page like http://www.cs.unc.edu/~sadasdf normally looks like this (in Firefox):
With the toolbar installed, I get this page:
There’s a few things I would point out:
- The first several links all provide ways to navigate or search unc.edu. I’m offered the option to go to www.unc.edu, or www.cs.unc.edu, or to search on www.cs.unc.edu for some words.
- Note that the toolbar took my nonsense phrase “sadasdf” and segmented that phrase into a more useful phrase “sad asdf” to search for. For “mattcutts” it suggested “matt cutts” and for “mygoodpage” it suggested “my good page”. That’s really helpful for a non-savvy user because it offers a search which may uncover the information that the user is looking for.
- There is a “Why am I seeing this page?” link.
If you click on the “Why am I seeing this page?” link, you get a page with more info, including how to turn the feature off:
I counted and it was three mouse clicks (click on a picture of a wrench, click to uncheck a box, click to save) to turn off the feature. Try to load a non-existent page, and I’m back to the standard 404 page that IE gives:
So my short summary is:
- If you’re a user and you don’t want help with 404 pages, it’s very easy to turn off just this feature (or don’t install the Google toolbar).
- If you’re a webmaster, customized 404 pages should continue work fine. If you want to be sure that users see your 404 page, make it 512 bytes or longer.
Bonus tip: Most of the people that read my blog use Firefox instead of Internet Explorer. If you want some similar functionality on Firefox, I like to use the ErrorZilla extension. It’s a handy little plug-in that gives you error pages like this:
I find the ErrorZilla plug-in really useful, even as a power user.