Because the Stanford web servers require encryption using SFTP, and WordPress’s built-in method of installing and implementing a plug-in uses FTPS, you cannot install plugins from directly within WordPress.
Instead, you need to manually install the plugin.
Here’s what you need to do:
1) Download the plugin to your Desktop.
2) Unzip the plugin.
3) Open an SFTP program like SecureFX or Fetch, log in, and change the plugin directory for your WP instance:
The directory should be something like “/afs/ir/group/groupname/cgi-bin/wordpressdirectory/wp-content/plugins” (substitute groupname for your real group name; wordpressdirectory for your real WP directory name)
4) Drag the plugin folder from your Desktop to the Remote Site side of SecureFX/Fetch.
5) In WordPress, go to your Dashboard (http://www.stanford.edu/group/groupname/cgi-bin/wordpressdirectory/wp-admin)
6) Click Plugins.
7) Locate the installed plugin and click Activate.
Your plugin is now activated!