Few things frustrate site visitors more than finding an error page where they expected to find useful content. The default 404 page that browsers encounter offers little more than an apology about the failure.

Many websites have shifted how they present the 404 page in recent years. They use the 404 to help the visitor get back on track, even going so far as to turn the experience into a little branding opportunity.

Microsoft wants to help more sites make their 404 pages useful when encountered. Their Live Search team tackled the page not found problem, and came up with their Web Page Error Toolkit.

They said the Toolkit, a customizable web application, looks at the keywords from a search that led to the 404 page. It returns a list of search results that may help the visitor get what they wanted to find. More on that from the Windows Live Dev blog:

The Toolkit is a customizable ASP.net application that replaces the default error page on your IIS server. The Toolkit enables you to use Live Search (or any search engine) to return results for the specified domain and locale, control the number of results returned on your page, choose whether to offer spelling corrections, and customize your error message.

You also have the option of choosing from several keyword extraction strategies that are included with the install, or providing your own implementation.

A mistake leading to a 404 does not have to be the end of someone’s experience with a website. Good implementations of this kind of get-back-on-track strategy could even turn a lost visitor into a converting customer, making the Toolkit worth a look for site publishers.

One of the better examples of a site giving its visitors a chance to get back on track resides at the Weather Channel’s website.  It’s a mini homepage that lets people know that, while their original request cratered on arrival, they can still get to forecasts, web search, and other links and services at Weather.com.

Some sites take the idea of spiffing up the 404 page to greater heights. The Royal Pingdom blog showed 17 examples of this today, ranging from flowcharts to President Bush to cut-up magazine text ransom notes.

One of the worst 404 examples comes from one of the best known tech companies out there. Google’s 404 page simply says Not Found, and does not even link back to Google.com.