Error Message: The File C:\W95undo.dat Cannot Be Read (137940)



The information in this article applies to:

  • Microsoft Windows 95

This article was previously published under Q137940

SYMPTOMS

When you try to uninstall Windows 95, you may receive one of the following error messages:
- The file C:\W95undo.dat cannot be read.
Error Code -6: Unexpected end of file.
- The file C:\W95undo.dat is invalid or incomplete.
Error code -4: Invalid signature.

CAUSE

The W95undo.dat file is missing or damaged. You cannot uninstall Windows 95 automatically if this file is missing or damaged.

RESOLUTION

To restore your previous version of Windows, follow these steps:
  1. Restart your computer using an MS-DOS boot disk that contains the Sys.com file.
  2. At the MS-DOS prompt, type the following line and then press ENTER:

    a:sys c:

    NOTE: If drive C is compressed, substitute the letter of the host drive (such as H) for drive C.
  3. Delete the Windows folder.

    NOTE: The Windows folder may contain files use by other Windows-based programs. If you delete the Windows folder, you must reinstall all your Windows-based programs.
  4. Reinstall Windows 3.x.

MORE INFORMATION

When you install Windows 95, you are prompted to back up the current system files. If you choose to do so, the Windows folder and all its contents are backed up to a hidden, compressed file called W95undo.dat. This file is used to restore the previous version of Windows.

Modification Type:MajorLast Reviewed:12/17/2000
Keywords:KB137940