There may be situations in which you need to reinstall Microsoft Windows to
troubleshoot a problem possibly related to file corruption or accidental
deletion of files from the Windows directory or the Windows SYSTEM
subdirectory. In most cases, it is not advisable to simply reinstall over
an existing Windows installation because with that procedure, some files
may not be properly updated.
Installing Windows to a new directory ensures a "clean" installation;
however, any modifications to Windows initialization (.INI) files or the
registration database (REG.DAT) are lost with such an installation. Also,
programs that install files into the Windows directory, such as Microsoft
Word for Windows and Microsoft Excel, cannot run from the new copy of
Windows. Any Windows-based applications must be reinstalled under the new
installation of Windows. Furthermore, any customization of Program Manager
groups, desktop colors and wallpaper, screen-saver settings, and other
user-defined environment settings must be re-created.
Use the following steps to reinstall Windows 3.1 without losing current
settings, such as .INI and REG.DAT file modifications, customized Program
Manager groups (.GRPs), and other desktop settings.
Install Windows into a new directory, such as C:\WIN. Verify that
Windows runs from this new directory.
If Windows ran during installation but does not run from this new
directory, something has changed on the computer, or file corruption
has occurred since Windows was installed. The following causes
should be considered:
Changes to the path
Deletion of files from the Windows directory
Low conventional memory
In this new installation, rename the .GRP files using .GRN, the .INI
files using .INN, and the .FOT files (located in the Windows SYSTEM
subdirectory) using .FOZ. Rename the REG.DAT file using REG.DAN. To do
this, quit Windows and type the following commands at an MS-DOS command
NOTE: The *.FOT files have an internal direct path to the *.TTF files,
which if copied to the old C:\WINDOWS\SYSTEM subdirectory, can create
problems with the fonts after the C:\WIN directory is removed.
Remove the Read-Only attribute from any files in the C:\WINDOWS and
C:\WINDOWS\SYSTEM directories. Copy all the files from the new
installation into the original Windows directory (C:\WINDOWS) by
typing the following at an MS-DOS command prompt:
If Windows now runs from the C:\WINDOWS directory, the reinstallation
has been successful, and no settings were lost. To save disk space,
delete the C:\WIN directory from File Manager or from MS-DOS version 6.0
or later using the DELTREE command. Also, delete files with the
extensions .INN, .GRN, and the file REG.DAN in the C:\WINDOWS directory,
and the files ending with .FOZ in the C:WINDOWS\SYSTEM subdirectory.
If Windows does not run, continue with the following steps.
Rename the original .INI files using .INO, and rename the .INN files
using .INI as follows:
Edit the PROGMAN.INI file and replace all occurrences of C:\WIN with
If Windows runs now, the problem is being caused by a corruption or
improper setting in one of the original .INI files. The best solution is
to back up all data files from Windows-based applications and then
reinstall the applications. This ensures the correct WIN.INI,
SYSTEM.INI, and directory settings for each application. Note that you
must re-create any customization of Program Manager groups and desktop
To free up disk space, delete excess files as shown in step 3 above.
If Windows does not run now, back up all application data files and
reinstall the applications under the new Windows installation after
renaming the .INN, .GRN, .FOZ, and REG.DAN files as follows: