When altPlugin first launches, it checks for an "altPrefs.txt" file in the "altPlugs" folder. If none exists, one is created.

The prefs file has the location and states (on or off) of all the stack plugin files currently loaded. The prefs file also contains other information, such as version numbers and update URL's (if they exist).

If "auto-check for updates" is checked in the preferences, then altPlugin will try and go online and check each plugin for newer versions. If a newer version of any plugin OR altPlugin itself exists, then a throbbing blue light will be displayed at the top left of the altPlugin palette. Clicking on the light will take you to the "Plugins" tab of the preferences window. There, on the right, will be the update status for each plugin. Selecting a plugin and pressing the "Update" button automatically replaces the old stack with the most recent version of the plugin from the designated server.