A boot sector virus is one which affects the master boot program by hiding in a boot sector of a hard drive or a floppy disk. This essay discusses the ways that the virus is spread, symptoms that may be exhibited by a computer affected by this virus and precautionary measures that one needs to take to ensure their computer is safe from this virus.

A boot sector virus will either infect or substitute a code of its own for that of either master boot record (MBR) or in other cases the DOS boot sector. The MBR in this case is a very small program which runs automatically whenever the computer is started. Its main function in the computer is to control the partition with which the computer boots from. It is usually situated on the first sector of a computer's hard disk (VCU, 2007).

A boot sector virus is very dangerous when in a computer because it affects the MBR which runs whenever the computer is started thus there is a high chance of the virus being loaded in the computer's memory. The virus can be easily spread from the memory to other parts of the computer.

A computer infected with a boot sector virus can show various symptoms which include problems related to retrieval of data. In other cases, data from a whole partition may disappear. The computer may become unstable or even fail to start up.

This virus may be spread by floppy disks that are infected.  It can be spread also through files downloaded from cross networks or may be attached on email files (Microsoft Support, 2010).

There are various methods to ensure that your computer is protected from boot sector virus or preventing it from further damage when it is already infected (Essortment, 2002). It is very important to install an anti- virus program on your computer for it to scan all files and remove viruses that might be present. An anti-virus is also important as it will monitor and detect any suspicious files in the computer.

It is also advisable to have your files backed up, so that they can be restored in case of virus damage. Original applications and all the system disks should always be write-protected to ensure that they are not affected by viruses. Any software that one wishes to install in their computer should be obtained from sources that are reputable and should not be  directly downloaded on the computer's hard disk but saved on a floppy disk which should then be locked and scanned for viruses. A computer which is infected should be immediately quarantined from others to avoid any transfer of files from it to other computers within the same network until it is disinfected.