This is strange, and I'm wondering if it's something I've done. We have a USB composite device that has two endpoints, one of which is used as a debug channel and one which is a mass storage interface. The mass storage interface works just fine.. however.. When our system (Windows 2000) crashes, it sometimes forgets that it needs the "USB Composite Device" driver and we have to manually reinstall it! This is somewhat tedious and painful, as you might expect, since it looks like that driver has to be reinstalled for each port that we're putting one of these devices on (ugh). I've looked over our debug interface driver code and I can't find anything that would cause Win2K to decide it doesn't need the composite interface any longer. Has anyone seen anything like this before? Does WinXP handle composite devices better? Are there any known issues with composite USB devices under Win2K? All help appreciated, I'm running out of hair to pull out!