Importance of error pages (404/500)

Why should you use them on your site

Error pages are important for several reasons, but mostly they ensure the user knows exactly what’s happening and what they can do when something unexpected happens on your site.

Is it important for SEO (Search Engine Optimisation)?

In short, yes. With everything else on your website you should always aim, as a priority, to make sure the site is friendly and easy to use for the user, SEO should always be a secondary concern. Having said that, if error pages don’t exist or they’re done incorrectly, search engines like Google, Bing and Yahoo may end up indexing pages incorrectly or deciding that your sites content is not relevant. This could result in your sites weight towards a particular subject being reduced or ignored completely.

How should they be done?

The Primary goal of these pages is to let you user know something has happened:

It might be a result of a missing page or file, a page or file that has been removed from your site or simply an external site linking to your site incorrectly. In these cases you will want to show a 404 error page.
It might, on the other hand, be the result of an issue with the site, some scenario the user has encountered that your site can’t handle, or simply something is wrong with the hosting environment or server. In these instances you’ll need a 500 error page.
In both cases you should always convey your message in a tone that doesn’t suggest the error is the fault, or was caused by, the user. The last thing you want to do is offend/scare the customer, or persuade them their time could be better spent elsewhere.

It’s important to maintain your sites identity (layout and structure). This gives the impression that the error is less of a concern and ensures the user knows they’re still on your site. Generally, it’s nice to add a bit of personality behind error pages, by giving them a more personal feel like adding an informal header or playful comment, helping them feel a little less forceful.

It’s important for you to give users a way out of these pages, somewhere to go or something to do if something’s gone wrong. If they’ve experienced an error they’re far more likely to stick on your site if you suggest what to do or suggest where they can go:

If the users trying to access content that your server can’t find (404), it might be important to provide alternative or similar pages
If the user experiences a server error (500) it might be important to give your user a link back to the previous page, to your sites help pages or contact form.
Both cases might just as easily be handled simply by maintaining your sites navigation; the user might just be inclined to try again or to try something different.

Is there anything else that can be done?

There’s plenty more that can be done. Most importantly though, Fix the error.

For example, if you’re missing a file, find and replace it or link to it correctly. If your site has had content removed from it or a page is being badly linked to then you might want to consider a 301 redirect, a type of message that tells the users system where content can be found and will redirect them when possible [we’ll have an article on our site about these soon]. If there’s a system error, there might be a process that needs investigating or tuning up.

What should be avoided?

Error pages, specifically 404 and 500 pages, are commonly done wrong. In the past I’ve seen a lot of websites introducing redirects, which suggest the URL the user is navigating to is wrong and the content is found elsewhere (bad implementation of 301 and 302 redirects).

It’s pretty straightforward to produce an error pages that simply displays an error message should something be wrong; In fact, PHP and .NET both have configuration settings that redirect errors to another page, they just don’t handle the error particularly well, and can result in the above issues.

CMS:42

Our new error system handles any errors you need it to on your site, presents this error page in the correct way and allows you to control the content of the error page from within CMS:42. It’s optimised for search engines and can be extended to provide dynamic content (e.g. suggested pages) depending on your needs.

Dan Peacey