Many site administrators use Google's excellent Webmaster Tools (also known as Google Search Console) to monitor their website for common issues. This free service from Google will alert you to common issues on your website, and also gives you invaluable information about how many times you are appearing in Google search results for various terms.
We are often asked about the section on 404 errors. The search console lists pages that no longer exist on your website, for which your website is returning a Page Not Found response (also known as a 404 error). The first instinct on seeing something listed as an 'error' is to think that it has to be fixed. However in the case of 404 errors this is not necessarily always the case. Let's dig a bit deeper into what these 404 errors actually are.
The first question to ask is how did this 404 error, or missing page, come to exist in the first place. The reason is that Google has previously found somewhere on the internet, either on your website, or another external website, where there is a link to this page. If Google finds a link to a page, and then finds the page doesn't actually exist, that is when it appears on this list.
As well as telling you the 404 error exists Google also helpfully tells you where it found the link. This is the first place to look. If the link is from your own website this is clearly a problem. You should fix the link on your own website so that you no longer refer to pages that don't exist. However often the link is from an external website, and you may not be able to get it removed or changed.
Now sometimes you have legitimately removed a page. Perhaps it relates to a service or product you no longer sell for example. In cases like these it's quite possible that returning a page not found is the correct response. It correctly tells visitors that the thing they are looking for doesn't exist on your website any more.
If you haven't entirely removed this product or service from your site, but instead perhaps you've just renamed it, or changed the page URL so it is better targeted for SEO, then you should setup a redirect on your website from the old URL to the new URL. This is good practice when changing any URL on your website.
There are various kinds of redirects you can setup, but most commonly you'll want to use the permanent redirect code, or a 301 redirect. Sometimes you may want to use a temporary, or 302 redirect, if you know you'll be changine the URL back to its original value soon (for example in the case of a temporary holding page).
Setting up a redirect will mean you are no longer serving a 404 error so naturally the error will drop off Google Search Console. One thing to keep in mind is it can take Google some time (often a few weeks) to catch up on processing all the changes you make, so don't expect to see any changes you make reflecting in the reports immediately.
Overall keeping on top of 404 errors is good practice, but it's important not to get too bogged down in worrying about the fact that they exist at all. In themselves 404 errors do not harm your site's SEO performance, and in some cases they are the correct response to return. But at the very least you should periodically review this report along with the other information on Google Webmaster Tools to ensure you're keeping on top of the basic housekeeping of maintaining your website.
Monitoring and resolving any items on Google Search Console is part of the service we can offer within our ongoing website SEO and maintenance packages. If you'd like to discuss further please give us a call on 01509 852 188 .
