how to access c++ com/activex files by using javascript ?

There are many experts here that will volunteer their time to help you if they can but you can't expect them to do everything for you. Also, I have no idea wahtsoever what DPFPCtlX.dll, DPFPDevX.dll, DPFPEngX.dll and DPFPShrX.dll are and you should assume no one here does. You need to be specific about what you neeed help with but I doubt that anyone here can help; it is unlikely that anyone here is familiar with that system. The best thing to do is to read the documentation and use other resources such as sample programs provided by the vendor.