Q74589: Hidden System Files and MS-DOS 5 and Later Upgrade

Article: Q74589
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:5.x,6.0,6.2,6.21,6.22
Operating System(s): 
Keyword(s): 
Last Modified: 17-DEC-2000

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The information in this article applies to:

- Microsoft MS-DOS operating system versions 5.0, 5.0a, 6.0, 6.2, 6.21, 6.22 
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SUMMARY
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The Microsoft MS-DOS Upgrade Setup copies the hidden system files IO.SYS and
MSDOS.SYS to the front of the root directory in the boot drive. If the previous
version of DOS had files called IO.SYS and MSDOS.SYS created by Microsoft, those
files will be deleted.

If the previous version of DOS has hidden system files by other names or that
were not created by Microsoft, they are moved to the first available space in
the root directory of the bootable hard drive. These files can then be deleted
after resetting the file attributes.

The following command will turn off the system file attribute, the hidden file
attribute, and the read-only file attribute of a file named IBMBIO.COM.

  attrib -s -h -r ibmbio.com

These files can also be deleted using MS-DOS Shell.

Additional query words: 6.22 5.00 5.00a 6.00 6.20

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS621 kbMSDOS622 kbMSDOS620 kbMSDOS600 kbMSDOS500 kbMSDOS500a
Version           : MS-DOS:5.x,6.0,6.2,6.21,6.22

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