If you’re on an Apache Server, with Mod_rewrite installed, you can create custom error messages for server errors.
Action Choices: [See Apache Manual]
Display Text
Redirect to External URL
Redirect to Local URL
Example lines of code for .htaccess file:
ErrorDocument 403 "Goodbye.
ErrorDocument 404 http://www.otherdomain.com/
ErrorDocument 404 /custom404.htm