title: How do I manually install or force the install of a plugin in Eclipse?
body: <p>How do I manually install a plugin in Eclipse? Or how do I force the installer to install a plugin, even when it doesn't want to?</p>
  
  <p>E.g., I am trying to downgrade a plugin (an update for which contained a bug that I cannot work with). I have tried going to <code>About Eclipse -&gt; Installation Details -&gt; Installation History</code> and selecting a previous configuration, but I get errors trying to revert to one. I have also downloaded the all-in-one update for the previous version of the plugin I want to roll-back. But if I go to <code>Install New Software -&gt; Add -&gt; Archive</code> then I can select the update, but when I try to install it I am told that the plugin I'm trying to install "will be ignored because a newer version is already installed".</p>
  
  <p>I need a way to install the plugin manually or force the installer to install the older version of the plugin. Doe anyone know how this can be achieved?</p>