How to Install an Extension in Joomla
This article explains how to install an extension in Joomla. If you need help uninstalling a extension in Joomla you can refer to the following KB article: How to Uninstall an Extension.

Joomla 1.6 and above 

1. Log into the Back End of your Joomla site.See How to Access the Back End of a Joomla Site.
2. Click on Extensions and then choose Extensions Manager.
3. In the Upload Package File section click Choose File and navigate to the location where your extension is located.
4. Click Upload & Install.
5. You should receive message that the installation was successful.

Joomla 1.5

1. Log into the Back End of your Joomla site. See How to Access the Back End of a Joomla Site.
2. Click on Extensions and then Install/Uninstall.
3. In the Upload Package File section click Browse and navigate to the location where your extension is located.
4. Click Upload File & Install.
5. You should receive message that the installation was successful.