My notebook toshiba q10 n250, dont have backup and or Any operating system ( after a format) so i tryed to install windows xp via an usb bootable, but now the bios dont recognize the hard disk (maybe drivers sata is missing, but dont know how to solve it), so i cant install windows. regards

Having a bootable USB is very essential, especially if you are a Netbook user. Using bootable USB to install an operating system (OS) not only makes the installation faster, but also saves a DVD.Creating or using an USB drive to install Windows operating systems is very easy if you follow the below mentioned steps.

Here we assume that you are using either Vista or Windows 7 to create a bootable USB.

1. Insert your USB (4GB+ preferable) stick to the system and backup all the data from the USB as we are going to format the USB to make it as bootable.

2. Open elevated Command Prompt. To do this, type in CMD in Start menu search field and hit Ctrl + Shift + Enter. Alternatively, navigate to Start > All programs >Accessories > right click on Command Prompt and select run as administrator.
3. When the Command Prompt opens, enter the following command:DISKPART and hit enter.LIST DISK and hit enter.Once you enter the LIST DISK command, it will show the disk number of your USB drive.
4. In this step you need to enter all the below commands one by one and hit enter. As these commands are self explanatory, you can easily guess what these commands do.
SELECT DISK 1 (Replace DISK 1 with your disk number), CLEAN, CREATE PARTITION PRIMARY,SELECT PARTITION 1ACTIVE,FORMAT FS=NTFS(Format process may take few seconds),ASSIGN,EXIT.
Don't close the command prompt as we need to execute one more command at the next step. Just minimize it.

5. Insert your Windows DVD in the optical drive and note down the drive letter of the optical drive and USB media. Here I use "D" as my optical (DVD) drive letter and "H" as my USB drive letter.

6. Go back to command prompt and execute the following commands:

D:CD BOOT and hit enter. Where "D" is your DVD drive letter.CD BOOT and hit enter to see the below message.BOOTSECT.EXE/NT60 H:(Where "H" is your USB drive letter)

7. Copy Windows DVD contents to USB.You are done with your bootable USB. You can now use this bootable USB as bootable DVD on any computer that comes with USB boot feature (most of the current motherboards support this feature).Note that this bootable USB guide will not work if you are trying to make a bootable USB on XP computer.

How to install Windows Vista/7 using bootable USB storage device Requires:
- Windows Vista/7 DVD 0r installation source (setup backup files)
- A 4GB USB 2.0 Storage device (Its recommeded to use USB 2.0 device for optimal performance)

• Plug your USB storage device.
• Run CMD and execute the following commands one by one.
• Diskpart

Run Disk parition utility

• List disk

To get disk index that is used to pefrom disk paritioning.

• Select disk 1

Selects disk to pefrom disk paritioning.

• Clean

Flush your existing all USB drive's partitions.

• Create parition primary

Creates a parition as primary parition.

• Format recommeded

Format your USB drive w/ recommeded parameters. (No need to worry about file system format)

• Active

Set the parition as active to hold bootmgr.

• Exit

To quit Diskpart utlity
Now copy all Windows Vista/7 files to USB storage device... thats all.

• Boot your PC w/ it, you can install Windows Vista/7 via bootable USB storage device.

Note: If you face any trouble to boot w/ it or unable to boot, try this
FIX.
I:\Boot\Bootsect.exe /NT60 I: Where I: is the drive letter of USB storage device