In order to redirect users to this page when a 404 error is triggered you have to enter a short line of code in your htaccess file.
Enter the general sattings of this stack page and make sure your folder name is set to 404 and the Filename to index.php
Open the Publishing tab of your Rapidweaver project and click in the Edit .htaccess file button.
Enter the following line of code and press Save and Upload to update your .htaccess file. You are done!
ErrorDocument 404 /404/index.php
Test your 404 page by entering a URL path in your browser that you know does not exist in your domain.
The page you are looking for is not here