MBRWizard as a Master Boot Record management utility program to directly update and modify the MBR.
In order to make certain you are able to perform MBR operations regardless of the Operating System you choose, I have versions available for Windows XP/2K/2003/PE/x64, DOS as well as Linux

MBRWizard was designed with a full set of features to help you solve most Master Boot Record (MBR) difficulties. We initially developed MBRWizard to resolve MBR problems caused by boot sector viruses, as well as those introduced by disk imaging products, such as Symantec Ghost and Backup Exec, Acronis True Image and Backup & Recovery 10, as well as StorageCraft ShadowProtect. Due to it's functionality and flexibility, MBRWizard has also become a popular utility for creating Windows 7 bootable USB flash drives, as well as repairing many types of MBR problems, especially those caused by disk-2-disk (d2d) and system backup and recovery applications.

MBR Operations:
1. Save or Backup MBR
2. Restore MBR from backup
3. Wipe MBR
4. Fix or repair corrupt MBR
5. Create a new MBR
6. Create/update the disk signature
7. Sort partition table
8. Copy Sectors
9. Delete existing MBR

Partition Operations:
1. Delete Partitions
2. Hide/Unhide Partitions
3. Set Bootable/Active Partition
4. Change Partition Type

Additional:
1. Securely wipe disk
2. Boot Menu: Select bootable partition
3. Read/write a persistent Status byte
4. Create ini file with disk and MBR info
5. Shutdown/Reboot the machine

How do I make a flash disk bootable? We need to first identify the flash disk, so start by running MBRWizard with the /list command: mbrwiz /list . After locating the flash drive, make note of the Disk # associated with the flash disk. Now, execute the following command, making sure the /disk=x variable corresponds to the flash disk #:
MBRWiz /Active=1 /Disk=x

The license of this software is Freeware, you can free download and free use this boot cd software.