By default, your X-Cart store's 404 "Page Not Found" page looks as follows:
Before going live with your store, you should check this page and make sure it looks as expected and provides your customers with the information you require. See:
Editing the 404 Page Content
To adjust the content of your 404 page:
Go to the Content Pages tab of the Pages & Menus page.
Click on the page name.
A page with the details of your store's 404 page opens.
Edit the page content as you require.
Regular text for 404 page: Edit the main 404 page content as you require.
Show сustomer relations e-mails on 404 page: Specify whether your store's customer relations email addresses need to be provided on the 404 page for your customers. These emails may be configured in your Store Profile (Store > Store Profile.
The page content will be updated.
Editing the 404 Page Layout
You can find out what kind of page layout your 404 page is using by going to the Content Pages tab of the Pages & Menus page in the Admin area and looking at the schematic diagram for the 404 page in the Layout column.
You can adjust the layout of the 404 page using the Storefront Builder:
In your store's Admin area, go to the Themes page (Design > Themes).
Click Customize storefront.
Your store's storefront area opens in the Storefront Builder.
In the address bar of your web browser, edit the URL to anything that will get your store's 404 page to be displayed. For example, if your store's URL is https://example.com, use a URL like https://example.com/1; provided that no such page actually exists in your store, you will get the 404 page.
Use the Storefront Builder facilities to adjust the page layout as you require.