BKF is known as "Backup Files". It is a built - in backup application used to create a proprietary backup format (BKF). It is also known as "Microsoft Tape Format" (MTF). It is a free utility available with Windows XP. Anyone can use it to take the backup of their valuable data from data loss situation. You can take backup of your files in Tape, Zip Drives, Floppy disks and Hard disks etc. This NTBackup utility supports Encrypting file system, NTFS hard links and junction points, alternate data streams, disk quota information, mounted drive and remote storage information. It saves NTFS permissions, audit entries and ownership settings, respects the archive bit attribute on files and folders and can create differential and incremental backups, backup catalogs, as well as Automated System Recovery.

A backup or the process of backing up files refers to preparing copies of data so that these copies may be used to restore the original after data loss event. Backup is the most important step to prevent data from data loss situations. There are two useful purposes of backup.

• Used to restore data in the situation of disaster (called disaster recovery).
• Used to restore small number of files in the situation of accidently deleted or corrupted due to any of the reason.

This is a default and can be renamed to any extension. This feature is not installed in "XP Home" by default. You can easily install it from the added value directory from CD of your "XP Home". After installing it you can use it to create a backup. You can take backup of your drives easily by using the NTBackup feature. Open Run and enter "NTBACKUP" command and press Enter and follow the instructions of the utility. If you make multiple backups then catalog of those backups is kept in your hard disk at "\Documents and Settings\All Users\Application Data\Microsoft\Windows NT\NTBackup\catalogs51" location.

Some of the reasons for corruption of BKF files are:

• Virus attacks.
• CRC errors.
• The backup file is unusable.
• Improper shutdown.
• Backup interruptions.
• Unrecognized media.