A bootable USB flash drive is a handy tool for diagnosing system problems. Generally, an MS DOS bootable drive is used to run many diagnosing and repairing tools for windows. For booting from USB drive, the drive itself first be made bootable i.e. a boot sector should be created on it. This can be done easily by using HP USB Disk Storage Format Tool. Format the drive using this tool to FAT32 file system and create MS DOS startup disk. Once you have created the bootable drive, follow these steps:
1. Change the BIOS booting option :
The bios booting order is by default set to boot from hard disk inside the system. But to enable booting from USB flash drive, you have to enable it in BIOS setting. In the boot option menu, make USB drive the first option. In some computer systems, USB drive is given as USB device, removable device or portable media.
2. Insert the USB drive in primary USB port :
The system generally checks only few ports before booting, so ensure inserting the USB drive into primary ports only. Never connect it via a USB Hub as the system will not be able to detect it before booting.
3. Turn on the computer :
As soon as you turn on the computer, press any key to enable booting from USB flash drive. After changing the BIOS boot order to USB drive, each time you start the computer, it checks for booting from USB drive. Make sure the USB drive has operating system on it and it has been made bootable i.e. it should have a boot sector. Now the system will boot from USB drive. Normally it will take around 10 to 15 minutes to boot from USB drive.