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With the hardware in place, you need to have installed the LPVR driver for the hand controllers, and there is one additional configuration that you may have to make before being able to use the controllers. This will require editing the SteamVR configuration steamvr.vrsettings. It is usually stored in C:\Program Files (x86)\Steam\config\steamvr.vrsettings for SteamVR installed via Steam or in the config subfolder of your standalone SteamVR installation. In this file, look around for the "steamvr" object and add the "activateMultipleDrivers": true setting to it. If the setting already exists, make sure it is set to true. The relevant part of the file will end up looking something like this:
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