I have just finished this smart card project in my company. May I remind you that the DLL file depends on the smart card reader/writer you are using and most of the time, it is bundled with the reader/writer. However, this DLL may not suitable for VB. In order to use it in VB, I can use wrapper to modify your DLL to suit VB. Anyway, this is something more technical, I can discuss with you later.