To install Jomsocial plugins ( Applications ), you can do it via Joomla Installer.
- Go to Joomla backend: http://domain.com/administrator
- Click on Menu Extensions - Extension Manager ( administrator/index.php?option=com_installer )
- When you are landed into Extension Manager page, you will see Upload Package File - Package File: Now click on Choose File. It'll open Windows Open dialog, select your plugin package file ( they are often named with prefix plg_''<name>.zip ). Than click Open button to choose it.
- After clicked on Open button you'll back to your Joomla! screen with selected file. And now click on Upload & Install. Wait for moment and you'll see message: Installing plugin was successful. Congratulation ! You have installed plugin success.