DOCUMENT:Q99148  20-FEB-2002  [msdos]
TITLE   :Microsoft Anti-Virus CHKLIST.MS Files Explained
PRODUCT :Microsoft Disk Operating System
PROD/VER:MS-DOS:6.0,6.2,6.21,6.22
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft MS-DOS operating system versions 6.0, 6.2, 6.21, 6.22 
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SUMMARY
=======

Microsoft Anti-Virus for MS-DOS (MSAV.EXE) and Microsoft Anti-Virus for Windows
(MWAV.EXE) create CHKLIST.MS files in most, if not all, of your directories.

MORE INFORMATION
================

CHKLIST.MS is a "checksum" file. A checksum is an error-detection scheme that
involves creating a sum of the bits in a set of bytes of data and using that sum
to later check for a change in the data. Checksums are commonly used in
communications software to check for data transmission errors.

In the case of Microsoft Anti-Virus, the CHKLIST file contains checksums for
certain files in the directory containing the CHKLIST file. The checksums are
based on the data contained in each file. The checksum is stored along with each
file's size, attributes, date, and time. This information is used by Microsoft
Anti-Virus during the Detect phase to check for changes to the files in the
directory.

The files are created (and updated) by Microsoft Anti-Virus during the Detect or
Detect And Clean scanning process if the Create New Checksums option is selected
in the Options dialog box.

Checksums are created for files with the following extensions:

   386
   APP
   BIN
   CMD
   COM
   DLL
   DRV
   EXE
   FON
   OV*
   PGM
   PRG
   SYS

Deleting the CHKLIST.MS Files
-----------------------------

The CHKLIST files can be deleted. To do this, press F7 in Microsoft Anti-Virus
for MS-DOS or choose Delete CHKLIST Files from the Scan menu in Microsoft
Anti-Virus for Windows.

If you disable the use of the CHKLIST.MS files, Microsoft Anti-Virus does not
check for unexpected changes in files. (It can scan files for known virus
signatures only.)

Additional query words: 6.22 6.00 subdirectory sub-directory 6.20

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS621 kbMSDOS622 kbMSDOS620 kbMSDOS600
Version           : MS-DOS:6.0,6.2,6.21,6.22

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