When LOOT is run, it will attempt to detect which of the supported games are installed. If a default game has been set, LOOT will run for it, otherwise it will run for the same game as it last ran for. If the relevant game cannot be detected, or if there is no record of the last game LOOT ran for, it will run for the first detected game.

LOOT’s initialisation can be customised using command line parameters:

--game=<game folder name>:
Set the game to run for. If the supplied game folder name is valid, the default and last game values are ignored. The default folder names are Oblivion, Skyrim, Fallout3, FalloutNV and Fallout4.
Set the path to use for LOOT’s application data storage. If this is an empty string or not specified, defaults to %LOCALAPPDATA%\LOOT on Windows and (in order of decreasing preference) $XDG_CONFIG_HOME/LOOT, $HOME/.config/LOOT or the current path on Linux.

If LOOT cannot detect any supported game installs, it will immediately open the Settings dialog. There you can edit LOOT’s settings to provide a path to a supported game, after which you can select it from the game menu.

Once a game has been set, LOOT will scan its plugins and load the game’s masterlist, if one is present. The plugins and any metadata they have are then listed in their current load order.

If LOOT detects that it is the first time you have run that version of LOOT, it will display a “First-Time Tips” dialog, which provides some information about the user interface that may not be immediately obvious.