Here are few tips that I thought I would pass along when modifying a password protected page or post in WordPress.

First, when you decide that you want to password protect a page or post, WordPress will natively include the following generic text on the page/post:

“This post is password protected. To view it please enter your password below:”

Simple, but may be a bit too generic for many. In my case, I need to modify the text a bit. To modify, you simply need to open /wp-includes/post-template.php using an ftp solution like FileZilla. You are searching for the following code:

function get_the_password_form() {
	global $post;
	$label = 'pwbox-'.(empty($post->ID) ? rand() : $post->ID);
	$output = '<form action="' . get_option('siteurl') . '/wp-pass.php" method="post">
	' . __("This post is password protected. To view it please enter your password below:") . '

	<label for="' . $label . '">' . __("Password:") . ' <input name="post_password" id="' . $label . '" type="password" size="20" /></label> <input type="submit" name="Submit" value="' . __("Submit") . '" />

	</form>
	';
	return apply_filters('the_password_form', $output);
}

To make changes, modify the highlighted text above. To learn more about this, visit http://wordpress.org/support/topic/password-protected-change-message.

Here’s another simple trick to spruce up your password protected page. When WordPress publishes your new password protected page/post, it will modify the page title. For example — PROTECTED: NAME OF PAGE. I personally find included “PROTECTED” in the title unnecessary. Here’s a simple way to remove it. You will need to open your functions.php file, and add the following code snippet at the top of your file just after <?php.

add_filter('protected_title_format', 'blank');
function blank($title) {
       return '%s';
}

If you want to learn more about doing this, visit: http://wordpress.org/support/topic/how-to-remove-protected-from-pw-protected-page-titles