1. USB version of ntdetect

Yet another ntdetect made by Microsoft, it is promoted for USB mass-storage device discovering, maybe it uses INT13H extension for recognizing USB storage. so NTLDR can save disk information in its LoaderBlock which will be transfer to OS kernel later.

 

2. CriticalDeviceDatabase & "boot" start type USB driver

Microsoft changed USB driver to "boot" start type to make sure USB stack to be initialized before kernel try to mark boot partition.

another important change is registry trick in CriticalDeviceDatabase. USB driver will create device objects when PNP manager find the compatible ID of the device matches to registry key in CriticalDeviceDatabase branch.

 

3. special version of usbhub.sys

a new version of usbhub.sys was add to XP Embedded Repository. unlike normal version of usbhub.sys, this driver can enumerate USB devices which attached to USB HUB at boot initialize time. so a USB Key insert to USB HUB could also boot up.

 

hope this will be clear.

enjoy it.