Virus in Master Boot

I use the program DRIVE IMAGE 2002 to make and retrieve the image of my Windows XP operating system. When the second diskette charge a screen indicates that you have a virus on MASTER BOOT. Despite that after several ENTER, it allows me to do image and recover without problems. I have used these same floppy disks on other computers with the same operating system and do not show these screens intermittent. I would like to see every detail of the process in order to eliminate this virus because I've tried and I may not XP. I ask because I am pretty clumsy clarity. Thanks and Regards.

Hello such as these?
I leave you a little information, I hope you will help.

What is a boot sector?
All disks and hard drives are divided into small sectores.El first section is called the boot sector and contains the Master Boot Record (MBR). The MBR contains information on the location of the partitions on the drive and reading boot the operating system partition. During the boot sequence in a DOS-based PC BIOS searches for certain system files, IO.SYS and MS-DOS.SYS. When the files have been located, then the BIOS looks for the first sector on that disk or drive loads and the need for Master Boot Record information in memory. The BIOS passes control to a program in the MBR, which in turn loads IO.SYS. The latter file is responsible for loading the rest of the operating system.

What is a boot sector virus?
A boot sector is a virus that infects the first sector, ie the boot sector of floppy or hard disk. The boot sector virus can also infect the MBR. The first PC virus in the wild was Brain, a boot sector virus that exhibited stealth techniques to avoid detection. Brain (virus) has also changed the volume label of the disk drive.

How to avoid the boot sector virus.
Commonly, infected floppy disks and subsequent infections boot sector the result of "shared" diskettes and software applications pirateado.Es relatively easy to avoid the boot sector virus. Most are spread when users inadvertently leave the floppy in the drive - which are found to be infected with a virus boot sector. The next time you boot your PC, the virus infects the local unit. Most systems allow users to change the boot order so that the system always attempts to boot first from the local hard disk (C: \) or CD-ROM.

Disinfection of boot sector virus.
Repair boot sector is best achieved by the use of antivirus software. Because some virus boot sector encrypt the MBR, improper disposal can lead to a unit that is inaccessible. However, if you're certain that the virus has only affected the boot sector and is not a virus encryption, the DOS command SYS can be used to restore the first sector. In addition, the TAG DOS command can be used to restore a damaged volume label and FDISK / MBR will replace the MBR. None of these methods is recommended, however. Antivirus software is still the best tool to draw cleanly and remove the boot-sector viruses with minimal threat to data and files.

Grateful but need to know the steps needed to clean the virus from the boot sector.

Since Windows press the Windows key (window) or + R Button Start, Run ... and type in the command line FDISK / mbr, this option (master boot record) or master boot sector is responsible for the successful boot of the operating system. This program takes care of loading into memory and execute the rest of the system. Also here are the bootloaders so that you can delete the entire contents of this sector so that in the next restart is reconstructed by the system.

Some viruses that are housed in the boot sector and then go to memory can cause irreparable damage to your computer. You can remove them with FDISK / mbr.