Noted That:

• To install correctly this if-modified-since.zip.
• Fisrt Download the if-modified-since.zip to your computer
• Extract/Open if-modified-since.zip to Your Computer.
• Then, Find readme.txt file inside if-modified-since.zip and Open readme.txt.
• Now, Read the Requirements of this plugin. Which Wordpress Version and PHP Version are required to run this Plugin in Your Wordpress Site.
• Then, Follow the the Tips Below.

Start the Tips:

1. First Download "if-modified-since.zip" Plugin to your Local Computer. (Click Download)

2. Then, Login to your "yourdomain.com/wp-admin" Dashboard.

3. Then, Click on "Plugins" + "Add New" from left sidemenu of Dashboard.

4. Now, Click on "Upload Plugin" button.

5. Now, Browse "if-modified-since.zip" Downloaded plugin from your computer, Where you downloaded if-modified-since.zip According to Step – 1 Above then, click on "Install Now"

6. Now, Click on "Active Plugin"

7. Then, See left sidemenu. "If Modified Since" folder is added on left sidemenu. Now, Click on "If Modified Since" folder.

   Noted that: If you do not see "If Modified Since" folder on left sidemenu then, see at left sidemenu "Settings" or "Tools".

8. Now you configure yourself oR Watch video tutorial below about If Modified Since Configurtions and Settings or How to work "If Modified Since" in your WordPress site.

After Activated Plugin According to Step-6 then,

1. Go to "Plugins" + "Installed Plugin" from Wordpress Admin Panel Leftside Menu.
2. or Direct go to: https://yourdomain/wp-admin/plugins.php
3. Then, Find "If Modified Since" Activated Plugin from Plugin List.
4. Then, Click on "Settings" from Plugin that is If Modified Since
5. Now, Edit/Add/Config the setting and Click on "Save Changes" button,

1. Upload the if-modified-since folder to the /wp-content/plugins/ directory
2. Activate the plugin through the ‘Plugins’ menu in WordPress
3. No need to configure, it just works!