When the server is unable to locate the file or page that is requested by the users, unexpectedly you can confront the Error 404 Meaning issue. However, the WordPress 404 Not Found error usually occurs due to one of the following reasons:
Maybe you have recently transferred your site to a new host.
You probably are trying to open an incorrect URL.
Poorly coded WordPress plugin could result in a 404 error.
Anyways, the potential solutions you need to implement to fix this issue are:
Clear browser history and cookies.
Set up your permalink properly.
Restore your .htaccess file.