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You will need to get at a minimum an IR receiver/drivers for your PC. You can get MCE IR receivers on eBay then set up your Harmony to emulate Msoft's MCE remote. An alternative is to get another PC type remote/receiver combination such as the MCE, Streamzap or Firefly among others and again set up your Harmony remote to emulate these models of controllers. The control is basic ie. not a mouse - but it will work for media apps. As an example, to whet your appetite, see http://www.streamzap.com/