DOCUMENT:Q62048  17-DEC-2000  [msdos]
TITLE   :Reasons for MS-DOS "File Allocation Table Bad" Error Message
PRODUCT :Microsoft Disk Operating System
PROD/VER:MS-DOS:3.x,4.x,5.x
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft MS-DOS operating system versions 3.1, 3.2, 3.21, 3.3, 3.3a, 4.0, 4.01, 5.0, 5.0a 
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SUMMARY
=======

There are basically six reasons why the "File Allocation Table Bad" error
occurs. These reasons are as follows:

 - The disk is not formatted, or incorrectly formatted.

 - An operating system other than MS-DOS is on disk.

 - There are defective disk sectors in the file allocation table (FAT).

 - There are invalid cluster numbers in the FAT.

 - There are lost clusters on the disk.

 - There is cross-linking of some files on the same cluster.

Using the CHKDSK /F command on the disk should repair the above problems. If it
doesn't correct the problem (that is, the same error is returned), you may want
to use a third-party disk recovery utility. As a final option, you may want to
reformat the disk.

Additional query words: tshoot 3.30 3.30a 4.00 4.00a 5.00 5.00a noupd

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS321 kbMSDOS400 kbMSDOS320 kbMSDOS330a kbMSDOS310 kbMSDOS500 kbMSDOS330 kbMSDOS401 kbMSDOS500a
Version           : MS-DOS:3.x,4.x,5.x

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