Often it is desirable to provide a custom error pages for pages that aren’t found or for which the user is denied permission to access.
You can do this with simple directives placed in a “.htaccess” file in your “public_html” directory.
ErrorDocument 401 /~login/401.html ErrorDocument 404 /~login/404.html
The 401 document is a web page to be displayed if a user attempts to view a document to which they do not have permission. The 404 document is a web page to be displayed if a requested document is not found.