Asking the company who made your IR remote control would get you your best response.

 I've received an Infra-Red remote control for my PC.  It plugs into the USB
 port and is supposed to advance presentation slides when prompted from the
 remote laser pen pointed at the now connected sensor.  The package did not
 include any software -- only said to plug into the USB port and begin
 changing slides.  The process currently does not change slides.  Is there a
 software setting I need to change?  Additional software I need to add?

Maybe it's stating the obvious, but you must be in slide show before it
works, and have you checked the battery?

Sometimes there is a button on either the USB dongle or the remote control
(sometimes both), which has to be pressed for 5 sec or so, so that the two
devices "recognize" the other. Sometimes this button is very small and has
to be pressed with the point of a pen.

But best solution would be to get a manual for the device (search the
website of the manufacturer).

Best regards,
Ute