Here's a quick game to play, it's called missed opportunity, first think of a web site then type in the URL, and then make up a random web page, say 404error.htm, type it in then hit return. What do you get? Chances are nine times out of ten you'll get the IIS, Zeus or the Apache 404 error page. It tells you nothing about the website and the first thing a user will do is hit the return button.
Server error messages
404 Error - The 404 or Not Found error message is an HTTP standard response code indicating that the client was able to communicate with the server, but the server either could not find what was requested, or it was configured not to fulfil the request and not reveal the reason why.
If a user gets a 404 error pages they more than likely to have arrived at the page from following an old link on Google or Yahoo, and if they're coming from a search engine they're looking to buy, and you'll have just lost a customer or a partner.
Most sites go through lots of different transformations in their life and removed pages are a fact of life. But every page on your site, real or deleted should be working for you. Particularly if the link the user followed was a link from a search engine for a product or service from your company. A standard default 404 error gives the wrong impression about your company, but it also loses you a customer.
I'm constantly amazed by the size of companies that don't have a customized 404 page, and that's everything from web design companies, through to marketing companies and up to Times 100 companies. And in general the bigger company the bigger the cost of a lost sale through a 404.
Communicating through a 404
Your 404 error page should tell a random customer about your company, it should apologise that they've come to the wrong page - it's only polite and it makes you into the helpful company - and ideally it should include a small site map. Remember there's no restriction on size, so you can fill the page with lots of information, however too much information will turn the user away, plus you don't know what device they're viewing your site from, it could be a mobile or a BlackBerry, so it helps to keep it text based. But don't make them too short Internet Explorer will not display 404 pages unless they are larger than 512 bytes.
Lastly don't refer to the page as a 404 error page, as nobody outside of the web knows, nor wants to know what a 404 is. However, just so that your web staff and techies don't go totally crazy - as you're messing around with their domain, and their diagnostics - then add the error number as a footer, with contact details for a technical/web person.
Examples of custom 404 page users
A good start is to look at how some of the good companies deal with 404's. eBay.co.uk and Dabs.com both use a mini description of themselves, and show what it is that they do, offer a search ability, and offer some help about where a user could look for more information. Amazon however gets it all wrong with "Looking for something? We're sorry. The web address you entered is not a functioning page on our site. Go to Amazon.co.uk's Home Page". Being too hard sell is probably not the best way to go, as you're unlikely to break a sale on the strength of one page, but just one or two lines will also have a user scurrying away.
To change the 404 error page in Microsoft IIS is quick, if you have access to the server. Go into Properties for the WWW service. Go to the Custom Errors tab. Find the listing for 404 and replace the default document with your own file. If your web service is hosted and you're using an ISP running IIS, you'll have to ask them to change this information for you. Just send them the URL of your 404 page, and ask them to set it as your custom 404 handler.
In Apache it's slightly more complicated. You need to create a file called .htaccess in the root directory of the server (the one you refer to as '/') and enter your error handlers in the following format, one per line:
ErrorDocument [3-digit code] [action]
For example, you can point to a custom 404 page like this:
ErrorDocument 404 /errors/sales404.html
Apache also allows you to create different pages for different languages and more information can be found here
Now you have your new 404 page make sure that it's kept up-to-date and that it reflects the main site. But the 404is just the tip of the iceberg, if you look in IIS you'll see that there are lots of other error pages, 3xx pages, 4xx, pages, 5xx pages, so use your new sales opportunity page and apply it to the other pages.
