How can I change email Notification for new user in WordPress

When admin add a new customer from back end manualy the email notification goes to new user.

The new user notification email is created and sent by the function wp_new_user_notification(), found in wp-includes/plugable.php

There is no filter hook within this funciton that will allow you to manipulate the output of the email, however you can of course overwrite any pluggable function via a plugin.

Note - You can only overwrite pluggable functions from within a plugin, not from within your theme.

This code will create the plugin which will be used instead of the one in wp-includes/plugable.php


<?php
/**
 * Plugin Name: User Email Notification
 * Plugin URI: http://astro-global.blogspot.in/
 * Description: This plugin helps you to Send email notification to user if user create by admin in back end. Easily customize, send Username, Password and link also.
 * Version: 1.0.0
 * Author: Sunil Sharma
 * Author URI: https://plus.google.com/u/0/+SunilSharma_007
 */
$pathsss = $_SERVER['DOCUMENT_ROOT'];
if(!defined('DS')){
    define('DS',DIRECTORY_SEPARATOR);
}
include_once $_SERVER['DOCUMENT_ROOT'].'/wp-load.php';
function email_notification_activation()
{
    if ( ! current_user_can( 'activate_plugins' ) )
        return;
}
function email_notification_deactivation()
{
    if ( ! current_user_can( 'activate_plugins' ) )
        return;
}
function email_notification_uninstall()
{
    if ( ! current_user_can( 'activate_plugins' ) )
        return;
}
register_activation_hook( __FILE__, 'email_notification_activation' );
register_deactivation_hook( __FILE__, 'email_notification_deactivation' );
register_uninstall_hook( __FILE__, 'email_notification_uninstall' );

if ( !function_exists('wp_new_user_notification') ) :
/**
 * Pluggable - Email login credentials to a newly-registered user
 *
 * A new user registration notification is also sent to admin email.
 *
 * @since 2.0.0
 *
 * @param int    $user_id        User ID.
 * @param string $plaintext_pass Optional. The user's plaintext password. Default empty.
 */
function wp_new_user_notification($user_id, $plaintext_pass = '') {
    $user = get_userdata( $user_id );

    // The blogname option is escaped with esc_html on the way into the database in sanitize_option
    // we want to reverse this for the plain text arena of emails.
    $blogname = wp_specialchars_decode(get_option('blogname'), ENT_QUOTES);

    $message  = sprintf(__('New user registration on your site %s:'), $blogname) . "\r\n\r\n";
    $message .= sprintf(__('Username: %s'), $user->user_login) . "\r\n\r\n";
    $message .= sprintf(__('E-mail: %s'), $user->user_email) . "\r\n";

    @wp_mail(get_option('admin_email'), sprintf(__('[%s] New User Registration'), $blogname), $message);

    if ( empty($plaintext_pass) )
        return;

    $message  = sprintf(__('Username: %s'), $user->user_login) . "\r\n";
    $message .= sprintf(__('Password: %s'), $plaintext_pass) . "\r\n";
    //$message .= wp_login_url() . "\r\n";
    $message .= site_url() . "/sign-in/";

    wp_mail($user->user_email, sprintf(__('[%s] Your username and password'), $blogname), $message);

}
endif;
?>

Create a Custom “Lost Password” Email in WordPress

Create a Custom “Lost Password” Email in WordPress : 

We’ve all done it. Not being able to remember passwords is one of the most annoying things about having so many website accounts across the internet. Fortunately, browsers nowadays let you save usernames and passwords for most websites so you don’t have to worry about losing login information that much. However, it does still happen. If you allow user registration on your WordPress site, users will inevitably need to reset their password at some point.

WordPress provides a default password-reset process that involves the user entering their username or email into a form. Once the form is submitted, WordPress sends an email to the user with that username/password that contains a link to reset their password. Once reset, the user can log in using their new password. The thing is that the canned email for this purpose is rather plain. The bright side, though, is that, like most things, WordPress gives us a way to customize this email. The code below does the following:

1. Changes the “From” email address. This would be the email any reply is sent to.
2. Changes the “From” name. This shows the recipient who the email is from.
3. Changes the email subject.
4. Changes the content type of the email to HTML so we can use markup within the message. Before, it was a plain-text message.
5. Creates a custom message to use in the email body. This process involves retrieving the user’s data based on their email/username, assembling a URL with appropriate query arguments so WordPress can do the password reset, and adding a custom message with the link to reset the password. The only part you’ll change is the message at the bottom; almost everything else needs to remain the same to work. Just make sure to include the link that lets the user actually reset the password.

Add this code in functions.php :

1. <?php
   //* Change "From" email address
   add_filter( 'wp_mail_from', function( $email ) {
       return 'hello@mydomain.com'; });
   //* Change "From" email name
   add_filter( 'wp_mail_from_name', function( $name ) {
       return 'My Website'; });
   //* Change Subject
   add_filter( 'retrieve_password_title', function() {
       return 'Password Recovery'; });
   //* Change email type to HTML
   add_filter( 'wp_mail_content_type', function( $content_type ) {
       return 'text/html'; });