To reset the settings outside of the game, you'll need to remove one of the registry files for the game. Before doing this, please make sure you backup your registry first.
- Open the Run box with the keyboard combination Windows key + r.
- In the Run line, enter “regedit” (without quotes)
- Click 'OK'
- Say 'Yes' to User Account Control (Windows Vista/7/8.x/10)
- Select File, then 'Export'
- Save this file somewhere you can find it and name it. This is your registry backup if you need to revert back to it.
- Once you've saved your registry, navigate to HKEY_CURRENT_USER\Software\Trion Worlds\ and find the folder named 'Atlas Reactor'.
- Right click the 'Atlas Reactor' folder and select 'Delete'.
- Once this is done, close the Registry Editor and launch the game again. The game will now be using default settings.