How to make a USB drive bootable

These steps must be done on a Windows 7 or Server 2008 computer.

WARNING!
This process will permanently erase any data on the USB flash drive!

1. Start an elevated command prompt (hint: right-click, run as administrator).

2. At the prompt, type diskpart and press ENTER. DiskPart starts.

3. At the DISKPART> prompt, type list disk and press ENTER. DiskPart lists the available disks.

Microsoft DiskPart version 6.1.7600

Copyright (C) 1999-2008 Microsoft Corporation.

On computer: %COMPUTERNAME%

DISKPART> list disk

Disk ### Status Size Free Dyn Gpt

——– ————- ——- ——- — —

Disk 0 Online 232 GB 0 B

Disk 1 Online 29 GB 0 B

4. Locate the disk that matches the characteristics of your USB drive. In this example, the USB drive can be identified by its size (usually smaller than the rated size of the disk) and is assigned as Disk 1.

5. Type select disk n and press ENTER, where n is the appropriate disk number. All further actions will now target this disk.

DISKPART> select disk n

Disk n is now the selected disk.

6. Type clean and press ENTER. The partition tables are zeroed out, putting the disk in an “uninitialized” state.

DISKPART> clean

DiskPart succeeded in cleaning the disk.

7. Type create partition primary and press ENTER.

DISKPART> create partition primary

DiskPart succeeded in creating the specified partition.

8. Type list partition and press ENTER. There should only be one partition.
Type select partition 1 and press ENTER. Partition 1 is selected for further actions.

DISKPART> list partition

Partition ### Type Size Offset

————- —————- ——- ——-

* Partition 1 Primary 29 GB 1024 KB

DISKPART> select partition 1

Partition 1 is now the selected partition.

9. Type active and press ENTER. This assigns the partition as bootable.

DISKPART> active

DiskPart marked the current partition as active.

10. Type format fs=ntfs quick and press ENTER. This performs a quick format of the partition.

DISKPART> format fs=ntfs quick

100 percent completed

DiskPart successfully formatted the volume.

11. Type assign and press ENTER. This assigns a drive letter to the partition.

DISKPART> assign

DiskPart successfully assigned the drive letter or mount point.

Type exit and press ENTER to leave DiskPart.

Credits: K.W.