Custom 404 error issues with Apache - the ErrorDocument is 404 as well

Whatever url you enter as the default 404 page must be either absolute or relative from the root folder : That's why some make the mistake of treating its url like the rewrite engines' url which is relative from the folder where .htaccess is located.

Instead of adding them to your .htaccess file, you can add them to any of your virtual host files.

<VirtualHost *:80>

    DocumentRoot /var/www/mywebsite

    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined

    ErrorDocument 404 /error-pages/404.html
    ErrorDocument 500 /error-pages/500.html
    ErrorDocument 503 /error-pages/503.html
    ErrorDocument 504 /error-pages/504.html

</VirtualHost>

Where error-pages is a subfolder in the mywebsite folder, containing the custom error pages. Make sure you restart your apache to view your changes.

$sudo /etc/init.d/apache2 reload

.htaccess files are disabled by default in Apache these days, due to performance issues. When .htaccess files are enabled, the web server must check for it on every hit in every subdirectory from where it resides.

Just figured it was important to note. If you want to turn on .htaccess files anyway, here's a link that explains it:

http://www.tildemark.com/enable-htaccess-on-apache/

The ErrorDocument directive, when supplied a local URL path, expects the path to be fully qualified from the DocumentRoot. In your case, this means that the actual path to the ErrorDocument is

ErrorDocument 404 /JinPortfolio/error/404page.html

When you corrected it in your second try, the reason you see that page instead is because http://localhost/error/404page.html doesn't exist, hence the bit about there being a 404 error in locating the error handling document.