If we talk about error message at all you should keep one simple rule in mind - Provide an error message that is clear and easy to understood in no time.
‘If your user can’t find it, s/he can’t use it, buy it or whatever’
Turn your 404 pages into opportunities..
Sending user to a 404 page without helpful information and links is like casting your user adrift.
Quite a lot of people recommend redirecting your 404 page just to your homepage, sure you can do this but it’s for sure the laziest option. There is so much more you can do.
How to deal with this problem?
Well first of all monitor and analyze your error pages. E.g. on the table of crawl error pages of the Google Webmaster Tools you can easily see your error pages and incoming links to these pages.
And as so often – it bears repeating - A site's URL structure should be as simple as possible. And if you have a simple URL structure it’s no problem providing the user helpful links.
What you should do – first rule - Instead of just saying a page is not found, your site should explain why that’s the case and be of assistance.
- Let the user know they are on a 404 page – And in order to capture the users’ attention be creative in speech and writing and also visual elements
- Explain why the page is showing up, what may have gone wrong e.g. bad link or typed in the wrong URL
- Stay consistent and provide your regular site navigation on your 404 page
- Your aim should be redirecting your user to another page what may have the content the user is looking for. Link to popular products, topics, landing pages as well as the homepage if it's not already accessible by your navigation.
- Offer a search engine that customers can use to find the right page
- Ask the user to help – Add an email link so that visitors can report problems, missing pages, and so on
- If you have an e-commerce website - This is an opportunity to show your popular and or fitting items, based on the ‘bad’ or ‘wrong’ URL
This is by no means an exhaustive list, but it should get you started in the right direction.
As I already said, errors happen, and you must be prepared. Things will go wrong that's the way things go - in real life and online. No matter how carefully you plan and develop your site, no matter how much testing you do, users will always come across difficulties and errors. What counts is how do you handle these unavoidable situations!
You have to give a hand to your users and customers when they are most irritated and maybe annoyed and you have to help them feel good and orientated again. The level of online patience and understanding is decreasing and users have a world of choices just one click away - ‘If they can’t find it, they can’t use it, buy it or whatever’
Unique Examples I'd like to share with you even if they do not follow my tips: