This is a resolution to the Error 404 that you get when your landing page is working but all of the other pages are failing work giving you an error 404.
Something that looks a little like this 
So to solve this issue you need to login to your FTP manager and browse to the root folder where you installed your WordPress site, it can be inside the public_html if you are on cPanel / CWP or httpdocs folder if you are on Plesk.
Create a file and name it ".htaccess" file without the quotes and if it already exists edit it then add the following code.
# BEGIN WordPress
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
# END WordPress
This should solve the problem.
