Magento Connect Manager

Magento Connect Manager (or Magento Downloader) is standalone Magento installer to manage installation and updates of Magento Connect extensions and core Magento modules.

Typically, it is available at /downloader/ URI from root of your Magento URL and can be accessed from System > Configuration > Magento Connect > Magento Connect Manager:

It requires the same authorization as for Backend:

For detailed instructions on using Magento Connect Manager you can refer to comprehensive Installing and Managing Magento Connect Extensions guide.
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