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Q100853: IO.SYS & MSDOS.SYS File Sizes Don’t Change After Uninstalling

Article: Q100853
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:6.0
Operating System(s): 
Keyword(s): 
Last Modified: 22-NOV-1999

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The information in this article applies to:

- Microsoft MS-DOS operating system version 6.0 
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SYMPTOMS
========

If you remove MS-DOS 6 Upgrade using the Uninstall disk you created during
installation, IO.SYS and MSDOS.SYS still have the MS-DOS 6 file sizes (the
original date and time are correct).

CAUSE
=====

This situation occurs because Uninstall overwrites the MS-DOS 6 IO.SYS and
MSDOS.SYS files with the previous versions of IO.SYS and MSDOS.SYS but does not
delete the MS-DOS 6 files first (nor does it truncate the files after
overwriting them).

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

Although this problem occurs with other versions of MS-DOS, the following table
only shows the files sizes before and after installation and uninstall with
MS-DOS 5.0 and MS-DOS 6.0.

                                               MS-DOS 5 after
  File           MS-DOS 5        MS-DOS 6     Unstalling MS-DOS 6
  ---------------------------------------------------------------

  IO.SYS           33430          40470              40470
  MSDOS.SYS        37394          38138              38138

Additional query words: 6.00

======================================================================
Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS600
Version           : MS-DOS:6.0

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