I'm working on a device that emulates a k/b, mouse, and one other custom interface. Btw, the custom interface was working fine, I'm just extending the existing firmware.
It did not work on the first attempt, so I started cutting it up, until I reduced it to just one interface, kb, with all the descriptors mimicking those of the actual USB keyboard by Dell. it works. The k/b shows up in device manager as an "HID-keyboard". However, as soon as I replace the Dell's VID with mine (0x223E) it does not work anymore. It does not show up in the dev. manager, and following the successful (yes!) enumeration the USB goes completely idle, with no interrupt requests coming at all. The only remaining activity on the bus are SE0 at 1 ms intervals.
Does it mean Windows maintains a list of VIDs that it is going to recognize? I have Windows XP SP3.