Drive Is No Longer Bootable After Restoring Root Directory (100374)


The information in this article applies to:

  • Microsoft MS-DOS operating system 6.0
  • Microsoft MS-DOS operating system 6.2
  • Microsoft MS-DOS operating system 6.22
  • Microsoft Windows 95
This article was previously published under Q100374
NOTE: This information applies to both Microsoft DoubleSpace and Microsoft DriveSpace. For MS-DOS 6.22 and Windows 95, use DRVSPACE in place of DBLSPACE in all commands and filenames.

SYMPTOMS

When you back up the root folder of drive C (or your DoubleSpace host drive, if drive C is compressed) and then later restore the files, you may no longer be able to boot your computer from drive C. When you use Microsoft Backup or Microsoft Backup for Windows in MS-DOS 6.x, this problem occurs if you clear the following options (which are selected by default) in the Special Selections dialog box when you restore the files:
  • Exclude Read Only Files
  • Exclude System Files
  • Exclude Hidden Files

RESOLUTION

Using MS-DOS 6.x or Windows 95 Without Dual Boot

To work around this problem, start your computer with the MS-DOS 6.x Upgrade Setup Disk 1 or Windows 95 Startup disk (Emergency Boot Disk) in drive A, and use the SYS command to make drive C bootable. For example, type the following command at the MS-DOS command prompt:

a:\sys a: c:

NOTE: If drive C is compressed and is currently mounted, you need to use the SYS command to make the host drive for drive C bootable.

Using Windows 95 with Dual Boot

To work around this problem when you are using Windows 95 and dual-booting to MS-DOS 6.x, follow these steps:
  1. Start your computer with the MS-DOS 6.x Upgrade Disk 1 in drive A and create a backup copy of the Windows 95 Msdos.sys file. To do so, type the following commands:

    a:\attrib c:\msdos.sys -s -h -r
    copy c:\msdos.sys c:\msdos.xxx

  2. Use the SYS command to make drive C bootable. For example, type the following command at an MS-DOS command prompt:

    a:\sys a: c:

    NOTE: If drive C is compressed and is currently mounted, you need to use the SYS command to make the host drive for drive C bootable.
  3. Remove the system, hidden, and read-only attributes from the Io.sys, Msdos.sys, Io.dos, and Msdos.dos files by typing the following commands:

    a:\attrib c:\io.sys -s -h -r
    a:\attrib c:\msdos.sys -s -h -r
    a:\attrib c:\io.dos -s -h -r
    a:\attrib c:\msdos.dos -s -h -r

  4. Delete the Io.dos and Msdos.dos files by typing the following commands:

    del c:\io.dos
    del c:\msdos.dos

  5. Create copies of the Io.sys and Msdos.sys files with the extension .dos by typing the following commands:

    copy c:\io.sys c:\io.dos
    copy c:\msdos.sys c:\msdos.dos

  6. Start your computer with the Windows 95 Startup disk (Emergency Boot Disk) and use the SYS command to copy the Windows 95 system files to drive C. For example, type the following command at an MS-DOS command prompt:

    a:\sys a: c:

    If drive C is compressed and is currently mounted, you need to use the SYS command to copy the Windows 95 system files to the host drive for drive C.
  7. Restore the backup copy of the Windows 95 Msdos.sys file created in step 1 by typing the following commands:

    a:\attrib c:\msdos.sys -s -h -r
    copy c:\msdos.xxx c:\msdos.sys

MORE INFORMATION

When you are using MS-DOS 6.x, Microsoft Backup always backs up read-only, hidden, and system files by default, but does not restore them unless you specifically select the options to do so.

Although Backup restores the MS-DOS 6.x or Windows 95 system files (Io.sys, Msdos.sys, Dblspace.bin, and Command.com) to the root folder of your hard disk, the disk is not bootable. For an MS-DOS or Windows 95 disk to be bootable, Io.sys must occupy the first entry in the root folder. Backup performs a "safe" restore, which means that it copies a file being restored to a folder with a temporary filename, deletes the old file, and renames it to its correct name. Therefore, when Backup restores Io.sys, it no longer occupies the first two entries in the root folder.
Modification Type:MajorLast Reviewed:12/17/2000
Keywords:kbprb KB100374
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