On Fri, May 10, 2013 at 6:06 AM, Ruben J=F6nsson wrot= e: > I have seen something on the Microchip forum about Microsoft OS Descripto= rs > which include generic devices that communicates through WinUSB.sys. When = using > the correct descriptor, you should not need to make your own custom .INF = file. > > This is built in from Windows 8 but earlier OS's (from XP SP3, if I remem= ber > correct) can also benefit from this by using a specific certified .INF fi= le > (which installs WinUSB.sys without user intervention). The following is a good source. https://github.com/pbatard/libwdi/wiki/WCID-Devices Basically Windows 8 has the system provided inf file and WinUSB files built in. Windows Vista and Windows 7 have the WinUSB files built-in but will need Windows Update to get the system inf file to get this to work. For Windows XP SP3, you have to provide the driver package by yourself or use libwdi's Zadig to help you (one time efforts). But XP will soon be obsolete (next year) so probably it is time to start to migrate away from XP. --=20 Xiaofan --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .