404 errors indicate that the webpage you are trying to reach either can't be found or has been deleted. Don't worry, there are a few steps that you can take to restore the webpage (as long as the page has not been deleted).
Possible reasons why you may see a 404 error:
The page you were on in the B12 Editor is hidden and you selected to Preview or Publish (you can learn how to show a hidden page here).
The URL has changed (this can happen if a page has been renamed)
The URL no longer exists
The URL was mistyped
Here some fixes that you can implement depending on the reason outlined above:
Redirect the 404 error: Add page URL redirects for your domain to show a new page
Correct the link: You can rename the page URL back to the original display name
Restore the page: You can restore a page using a History snapshot, or if you've made any other changes since then, rebuild the page within your B12 website editor
If you need any help, please reach out to our Customer Support team!