Title: LH Add Headers
Author: shawfactor
Published: <strong>مئی 6, 2016</strong>
Last modified: مئی 2, 2017

---

Search plugins

![](https://ps.w.org/lh-add-headers/assets/banner-772x250.jpg?rev=1411420)

This plugin **hasn’t been tested with the latest 3 major releases of WordPress**.
It may no longer be maintained or supported and may have compatibility issues when
used with more recent versions of WordPress.

![](https://ps.w.org/lh-add-headers/assets/icon-128x128.png?rev=1411420)

# LH Add Headers

 By [shawfactor](https://profiles.wordpress.org/shawfactor/)

[Download](https://downloads.wordpress.org/plugin/lh-add-headers.zip)

 * [Details](https://bcc.wordpress.org/plugins/lh-add-headers/#description)
 * [Reviews](https://bcc.wordpress.org/plugins/lh-add-headers/#reviews)
 *  [Installation](https://bcc.wordpress.org/plugins/lh-add-headers/#installation)
 * [Development](https://bcc.wordpress.org/plugins/lh-add-headers/#developers)

 [Support](https://wordpress.org/support/plugin/lh-add-headers/)

## Description

A `304 Not Modified HTTP Header` tells your visitors that nothing has changed since
their last visit. This is important as without this header visitors may be downloading
your webpages from scratch each time, slowing down their experience and your site.

Generally if you do not pass `304 Not Modified HTTP Header` through your HTTP header,
crawlers will fetch your whole website and then compare the content of your site
with the already indexed content to check whether anything new has been updated 
on your website or not. But this process consumes a lot of your server resource 
and bandwidth.

You can know more about it [here](http://www.feedthebot.com/ifmodified.html).

#### Before reading any further

Before reading any further it is important to understand this plugin uses output
buffering, in fact the Etag sent by this plugin is a hash of the sites buffered 
content. If your site uses server side caching this plugin may break the caching
functionality. Therefore I suggest that you please **make sure** you have studied
the FAQ, before installation and activation.

## Installation

 1. Upload the entire `lh-add-headers` folder to the `/wp-content/plugins/` directory.
 2. Activate the plugin through the ‘Plugins’ menu in WordPress. That is it.

## FAQ

  Installation Instructions

 1. Upload the entire `lh-add-headers` folder to the `/wp-content/plugins/` directory.
 2. Activate the plugin through the ‘Plugins’ menu in WordPress. That is it.

  Will this plugin cause problem if you use server side caching?

Quite possibly depending on your setup. It could prevent caching or even break your
site if you are using server side caching (including Varnish). This plugin should
NOT be used on hosts like WPEngine or DreamPress as it will break caching.

  How do I check if it is working?

Install one of the the view live HTTP headers tools in your browser. Visit your 
website and then refresh the page. On your second visit the website should return
a 304 not modified response.

  Are there other reason why a 304 header is not being return when I haven’t changed
the content?

In order to to return 304 the hash of the returned content must be the same (IE 
the html must be identical between requests.
 Unfortunately, some plugin adding 
dynamic and varying content to each page output returned. Try disabling each plugins
to find the culprit.

  What are the benefits?

This helps visitors and search engines. If your page or post has not been updated
since the last visit, then your page will sent a `304 Not Modified Header`. On receipt
of this header search engines know nothing has changed (and therefore there is no
need to re crawl your site), likewise a normal visitors browser will get a 304 and
will use the browser side cache of the page (thus speeding up the visitors experience).

## Reviews

There are no reviews for this plugin.

## Contributors & Developers

“LH Add Headers” is open source software. The following people have contributed 
to this plugin.

Contributors

 *   [ shawfactor ](https://profiles.wordpress.org/shawfactor/)

[Translate “LH Add Headers” into your language.](https://translate.wordpress.org/projects/wp-plugins/lh-add-headers)

### Interested in development?

[Browse the code](https://plugins.trac.wordpress.org/browser/lh-add-headers/), check
out the [SVN repository](https://plugins.svn.wordpress.org/lh-add-headers/), or 
subscribe to the [development log](https://plugins.trac.wordpress.org/log/lh-add-headers/)
by [RSS](https://plugins.trac.wordpress.org/log/lh-add-headers/?limit=100&mode=stop_on_copy&format=rss).

## Changelog

**1.00 April 15, 2016**
 Initial release.

**1.01 May 05, 2016**
 Code improvement

**1.02 May 19, 2016**
 Fixed customiser issue

**1.03 June 22, 2016**
 Fixed documentation link

**1.04 April 30, 2017**
 Added class check

**1.05 May 10, 2017**
 Keep comments in outputted source

## Meta

 *  Version **1.04**
 *  Last updated **9 years ago**
 *  Active installations **10+**
 *  WordPress version ** 3.1.0 or higher **
 *  Tested up to **4.8.28**
 *  Language
 * [English (US)](https://wordpress.org/plugins/lh-add-headers/)
 * Tags
 * [cache-control](https://bcc.wordpress.org/plugins/tags/cache-control/)[caching](https://bcc.wordpress.org/plugins/tags/caching/)
   [expires](https://bcc.wordpress.org/plugins/tags/expires/)[headers](https://bcc.wordpress.org/plugins/tags/headers/)
   [last-modified](https://bcc.wordpress.org/plugins/tags/last-modified/)
 *  [Advanced View](https://bcc.wordpress.org/plugins/lh-add-headers/advanced/)

## Ratings

No reviews have been submitted yet.

[Your review](https://wordpress.org/support/plugin/lh-add-headers/reviews/#new-post)

[See all reviews](https://wordpress.org/support/plugin/lh-add-headers/reviews/)

## Contributors

 *   [ shawfactor ](https://profiles.wordpress.org/shawfactor/)

## Support

Got something to say? Need help?

 [View support forum](https://wordpress.org/support/plugin/lh-add-headers/)

## Donate

Would you like to support the advancement of this plugin?

 [ Donate to this plugin ](https://lhero.org/portfolio/lh-add-headers/)