Q120898: File Manager and Shell Report Total Size of CD-ROMs as 128 MB

Article: Q120898
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:3.x,4.x,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 3.1, 3.2, 3.21, 3.3, 3.3a, 4.0, 4.01, 5.0, 5.0a, 6.0, 6.2, 6.21, 6.22 
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SUMMARY
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File Manager and the MS-DOS Shell may report 128 megabytes (MB) as the total
size of a CD-ROM and zero (0) MB as the amount of free space. This occurs
because the Microsoft CD-ROM Extensions (MSCDEX) reports 128 MB as the capacity
of a CD regardless of the real capacity or true remaining free space on the CD.

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

MSCDEX reports 128 MB for the MS-DOS DISK INFO function call. This MS-DOS API is
used by File Manager and Shell. Although it is not difficult to find the
capacity of a CD-ROM, MSCDEX does not use this information. MSCDEX reports a
total of 65,535 clusters of 2 kilobytes each and 0 free clusters.

Additional query words: 4.00 5.00 6.00 6.20

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS321 kbMSDOS400 kbMSDOS320 kbMSDOS330a kbMSDOS621 kbMSDOS622 kbMSDOS620 kbMSDOS600 kbMSDOS310 kbMSDOS500 kbMSDOS330 kbMSDOS401 kbMSDOS500a
Version           : MS-DOS:3.x,4.x,5.x,6.0,6.2,6.21,6.22

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