Setup Checks for 6 Free Entries in the Root Directory (94413)

The information in this article applies to:
    Microsoft MS-DOS operating system 5.0
    Microsoft MS-DOS operating system 5.0a
    Microsoft MS-DOS operating system 6.0
    Microsoft MS-DOS operating system 6.2
    Microsoft MS-DOS operating system 6.21
    Microsoft MS-DOS operating system 6.22

This article was previously published under Q94413


The Microsoft MS-DOS Upgrade installation program (SETUP.EXE) starts, but is unable to completely install the upgrade.


SETUP.EXE checks the root directory of your startup drive (usually C) to determine if there is enough room for MS-DOS files in the root directory. In some cases, Setup may incorrectly determine that enough room exists. Setup starts, but is unable to complete the installation.


To work around this problem, remove unnecessary files from the root directory and rerun Setup.


You cannot have more than 512 entries (files or directories) in the root directory of an MS-DOS partition. Setup does not allow you to install MS-DOS Upgrade if you have 507 or more entries in the root directory (including hidden files). This ensures that MS-DOS Setup can create at least six entries.

In some cases, six entries is not enough. When Setup runs out of entries, the installation cannot be successfully completed. For example, if you are using PC-DOS, you have 506 entries in the root directory, and you install MS-DOS 6.x Upgrade in a new directory, Setup cannot successfully install all the files.

The information below lists all potential files and directories that may be placed in the root directory and under what conditions they are installed. Any combination of the factors listed below results in an incomplete installation.
    WINA20.386 is copied to the root directory if your computer is capable of running Microsoft Windows in 386 enhanced mode and you have Windows version 3.0 installed.
    If you are using IBM PC-DOS, the files IBMBIO.COM and IBMDOS.COM are no longer used but are not deleted. MSDOS.SYS AND IO.SYS are copied to the root directory as two additional files.
    If you choose a new directory when you install MS-DOS, an additional root directory entry is used.
    If AUTOEXEC.BAT and CONFIG.SYS are changed by Setup, the files AUTOEXEC.OLD and CONFIG.OLD are created in the root directory.
    Setup creates an OLD_DOS.1 directory.
    If use the /E switch to install both the MS-DOS-based and the Windows-based programs that ship with MS-DOS, Setup creates a WINDOWS directory. (This does not apply to MS-DOS 5 Upgrade).

Modification Type: Major Last Reviewed: 5/10/2003
Keywords: KB94413