My Smart Card is not being recognized as a smart card, but as a DFU Adapter. I have another one, same model, and it works just fine, but when I swap them, the other one LOADS a DFU Adapter driver, and then is not recognized as a smart card reader.  I have tried installation on both of my computers, with the same result.  Any ideas how I can make the computer recognize it at the correct device?You do not mention the make and model of your "Smart Card" reader device so i cannot for the moment be more specific than i am about to direct you. Here is a link to a specific card reader with similar issue of recognition. Reading through the steps for that device may assist you with your issues for yours.
http://militarycac.com/files/SCR331FirmwareUpdateProcedure.pdf
truenorthIt is the same reader; however, this fix is spposed to be for VISTA or Win 7.  This issue is not SUPPOSED to occur with XP.  This article is outdated, so the instruction is very difficult to follow.  I tried as best I could, and did arrive at the same conclusion as the pdf, but then when I tried it out on my XP machine, it STILL lists as a DFU Adapter instead of a smart card.