A 404 Error happens on your website when a page requested by a reader was not found on your blog. If you are a webmaster, it is important that you fix all the 404 errors which are happening on your blog as this could impact your index in Google search as well. Repair 404 Errors WordPress Plugin is a nice and useful plugin to have on your blog as it simply notifies you of any page or file requests that a user (or search engine) makes to your blog.
Once installed, you can see the plugin catching all the 404 requests on your blog. If it can’t find the right file or page it captures that failed request into the plugin so that you can easily go and fix the issue manually. To test the plugin, you can manually type a junk URL on your blog and you can see it listed in the plugin page.
After you fix the issue you can then hit the Repaired button to let the plugin know that you’ve handled the problem.
This plugin is pretty useful to fix all the 404 pages on your blog including any broken links.
Download Repair 404 Errors WordPress Plugin