GREAT! Now, that you know a few things about redirects, let’s check out the second problem, the 404 errors …

2. 404 errors

So, what are these 404 errors?

The 404 error is an HTTP status code which means that the requested web page could not be found on the server. This client-side error can be caused by many different reasons, such as broken links, incorrectly typed URLs, moved pages, deleted content, .htaccess problems, wrongly configures SSL certificates, memory limit issues, etc. In these situations you’ll have to use a nice custom 404 page to kindly redirect your visitors to a working page – usually the homepage or another content-related page – on your website. Not having a 404 page and displaying a simple “page not found” message will have a huge negative impact on your users’ experience.

And basically, this is the point where the 404 errors are becoming important. From a strictly technical SEO standpoint 404 errors aren’t really disastrous. In short term they won’t negatively impact your SEO efforts, but if there are too many and they persist, sooner or later your website will be abandoned by many frustrated users, and then my friend you may not continue ranking so well …

You’ll have to focus on two issues:

Issue #1: Finding and fixing the existing errors

First of all, you need to understand that there are two different situations: 404 errors encountered by human visitors and 404 errors encountered by search engines. Obviously, the search engine bots will encounter many 404s that human visitors will never get to. This is because they probably will crawl just about anything on your site, even links or pages which are invisible or inaccessible for human visitors.

The best way to identify the 404 error pages that search engines may encounter, is by logging in into their own webmaster-tool platforms to access the indexation reports, in which they will tell you which 404s they encountered. In your Google Webmaster Tools account check out the “Crawl -> Crawl Errors” section, and in your Bing Webmaster account go to “Reports & Data -> Crawl Information”.

Identifying the 404 errors encountered by human visitors is perhaps even more important. Don’t worry there are many useful tools that can help you to find the problematic URLs ... For example ...

https://www.deadlinkchecker.com/

And of course the unbeatable Google Analytics ...

If you have no content management system in place, you’ll have to create a custom report to detect and investigate 404 errors. You can choose to capture details using page level customization or events and I recommend you to use the former method (in my opinion viewing a 404 error page is definitely not an event).

If you are running a WordPress site, I strongly recommend you to use the MonsterInsights plugin, which is the most powerful Google Analytics plugin for WordPress sites and it’s definitely a MUST for WordPress-based websites.

MonsterInsights will automatically tag the 404 pages for you and if you go into your Google Analytics account you’ll find a ton of useful info about your 404 errors. All you have to do is to select “Behavior -> Site Content -> Content Drilldown” and search for “404.html”: