Internal linking is good for SEO and Google loves it. However, linking to 404 internal URLs could cause down rankings in Google SERPs. This issue has just been reported by a blogger in WebmasterWorld. We should be careful about this too.
Many of us have been aware of the importance of internal linking that can improve your pagerank as this can demonstrate that your contents is logical. However, if your post links to an 404 error URLs, it can likely be harmful to your SERPs in Google. This is still controversial but you need to take care of this in order to maintain or boost your ranking in SERPs.
Frankly, it is not good linking to unavaliable URLs and your webmaster tools account will show a lot of errors. This can decrease your traffic from search engines too. But, you can fix it with several tools that are free.
Here are some recommended tools that help you remove or 301 permanently redirect to new URLs:
This plugin is used for WordPress and it will scan your database and show you how many broken links your blog has. You can see and fix it easily. I love this plugin and you should give it a try and see how it can help improve your 404 errors.
Redirection is a WordPress plugin to manage 301 redirections, keep track of 404 errors, and generally tidy up any loose ends your site may have. This is particularly useful if you are migrating pages from an old website, or are changing the directory of your WordPress installation.
This plugin fixes all sorts of weird addons to your URL’s by automatically 301 redirecting to the permalink for that post, page, category or tag page.
A WordPress plugin that replies a 301 permanent redirect, if requested URI is different from entry’s (or archive’s) permalink. It is used to ensure that there is only one URL associated with each blog entry.
301 redirect is the most efficient and Search Engine Friendly method for webpage redirection. It’s not that hard to implement and it should preserve your search engine rankings for that particular page. If you have to change file names or move pages around, it’s the safest option. The code “301″ is interpreted as “moved permanently”.
These are great plugins but the last one is designed for non-wordpress blogs, not plugin. If you are using wordpress or non-wordpress blogs or websites, you can still use this script to do 301 permalink redirect.
Hope this can help you fix your 404 error and improve SERPs in Google search.