This tutorial will help us in learning how to create error pages in apache. We can customize the error pages based on different error codes that is writen in Apache server's Directive ErrorDocument Follwoing are the Three digit error code:

Apache error codes (401, 403, 404, 412, 500)

If we come accross an error , we can handle it in four ways as below:

1. Display a simple hardcoded error message
2. Display a customized message
3. Handle the problem by redirecting to an external URL
4. Handle the problem by redirecting internally a local URL-path

Note: The first option is default one and the 2-3 options are configured using the ErrorDocument Directive.

Let us create a custom error page for error code 404 (i.e. file not found error)

Step 1: First write an html page, say index.html to display the error message

Step 2: Now place this file inside the site's root directory

For example : path is = /var/www/html/projectrootdirectory/index.html

if we place this index.html file in some other subdirectory say Error

path = /var/www/html/projectrootdirectory/Error/index.html

Step 3: Now include apache server's directive ErrorDocument in the .htaccess file with the syntax as below:

  ErrorDocument error-code action

    1. ErrorDocument : it is the Directive
    2. error-code : (i.e. any of the 401, 403, 404, 412, 500)
    3. action : the path of your custom error page.

Note: for default action we can just write a message in a single quotes

OR

Find your Web server configuration file i.e. httpd.conf. In case of apache server your path will be

         /etc/apache2/apache2.conf

For Example: We can create custom error page for a site under following path

/etc/apache2/sites-enabled/000-default.conf

Below is the code that we will write in the 000-default.conf file

       <VirtualHost *:80>
              ServerAdmin admin@firstexample.com 
              ServerName firstexample.com
              ServerAlias www.example.com
              DocumentRoot /var/www/firstexample/public&#95;html
              ErrorDocument 404  /ErrorPages/404pagenotfound.html

               # Other directives here
          </VirtualHost>

Similarly we can maintain custom errror pages for the following error code 401, 403, 412, 500

For more information regarding apache custom error pages click the Link below.

http://httpd.apache.org/docs/trunk/mod/core.html