The BIOS may fail to properly enumerate USB bootable devices, which results in a blue screen and failure of USB boot. When troubleshooting USB boot failure, use the USBNTD.CHK tool and the following procedure to verify that the BIOS properly enumerates USB bootable devices.

To verify USB bootable devices

1. Copy USBNTD.CHK from the Value Add folder on the installation disk to the USB boot medium and rename it NTDETECT.COM.
2. Boot the device.
3. The tool displays the bootable devices identified by the BIOS.

   If bootable devices are found, the following output appears:

   Enumerating Interrupt 13 disks found on this system
   DriveSelect-MaxCylinders-SectorsPerTrack-MaxHeads-NumberDrives
   <NNN>-<NN>-<N>-<NN>-<NNN>
   ...
   <NNN>-<NN>-<N>-<NN>-<NNN>
   Enumeration done.  Press a key to continue...

   where <NNN>-<NN>-<N>-<NN>-<NNN> represents the drive characteristics for each bootable device.

   If the BIOS fails to find any bootable devices, the tool displays failure reasons and prompts the user to ignore and retry. Upon retry, the tool then enumerates any boot disks found on the system with their drive characteristics.

Failure to find bootable devices may indicate a problem in any of the following areas:

• BIOS
• USB storage medium
• motherboard

See Also

Booting from USB Devices in Windows XP Embedded Help

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