Windows 7 has introduced a new plug&play feature for smart cards: now when you insert a smart card in the reader Windows 7 tries to find a smart card driver (aka minidriver, see this for more info: http://www.microsoft.com/whdc/device/input/smartcard/sc-minidriver.mspx) that must be used for security related functions like Windows-Logon or digitally signing of documents.
Prerequisite for this kind of usage is that the card must be a cryptographic card, suitable for digital signature and encrytion and the manufacturer/issuer of the card, supporting this feature, must provide necessary drivers/software via Windows®-Update. Because most of the cards used by customers are not cryptographic cards, that cannot be compliant with that feature and doesn't have a suitable driver, the users see a message saying, that the installation of a driver for the smart card fails every time a smart card is inserted into the card reader.
Pay attention! This DOES NOT mean, that the installation of the driver for the card reader failed nor that the smart card or its driver has not been recognized. This means simply that installing a driver for that smart card was not successful because it isn't a cryptographic card. In such a case the non cryptographic smart card works correctly even if the driver has not been found.
To get rid of this at times annoying message, you may disable the Plug & Play service for smart cards.
Depending on the exact version of Windows 7, one (x86) or two (x64) registry entries need
to be edited or added:
Entering "dword:00000001“ instead of "dword:00000000“ as value for
"EnableScPnP“ would enable the service.