Installing Windows for Workgroups 3.11 and Windows 98 Second Edition on the same FAT32 partition

Thanks to a set of unofficial patches, it is possible to install Windows for Workgroups 3.11 on a FAT32 partition.

Prerequisites

• Windows 98 Second Edition installation media
• Windows for Workgroups 3.11 installation media
• OSR2FIX.EXE from https://www.vogons.org/viewtopic.php?t=31922 (TODO: Mirror)
• 311FAT32.COM from https://www.vogons.org/viewtopic.php?t=31922 (TODO: Mirror)

Procedure

1. Boot from the Windows 98 Second Edition installation media
2. Create a FAT32 partition
3. Install Windows 98 Second Edition to C:\WIN98SE
4. Install Windows for Workgroups 3.11 to C:\WFW311
5. Reboot into command prompt only
6. Edit CONFIG.SYS to look like this, moving the existing contents to the WFW311 section:
   

   [MENU]
   MENUITEM=WFW311
   MENUITEM=WIN98SE
   
   [COMMON]
   
   [WFW311]
   DEVICE=C:\WFW311\SMARTDRV.EXE /DOUBLE_BUFFER
   DEVICE=C:\WFW311\IFSHLP.SYS
   STACKS=9,256
   LASTDRIVE=Z
   
   [WIN98SE]
   

7. Edit AUTOEXEC.BAT to look like this, moving the existing contents to the WFW311 section and explicitly updating PATH with the location of the MS-DOS utilities:
   

   GOTO %CONFIG%
   
   :WFW311
   SET PATH=C:\WFW311;C:\WIN98SE\COMMAND;%PATH%
   C:\WFW311\SMARTDRV.EVE
   C:\WFW311\NET.EXE START
   GOTO END
   
   :WIN98SE
   
   :END
   

8. Run ATTRIB -R -H -S MSDOS.SYS
9. Edit MSDOS.SYS so that section Options key BootGUI is set to 0; this has the side-effect of ensuring PATH isn't messed with
10. Run OSR2FIX.EXE to extract its contents
11. In the extracted contents, run WIN3X.BUG\W3XSTART.EXE
12. Confirm modification of IO.SYS
13. Change to the C:\WFW311\SYSTEM directory
14. Run 311FAT32.COM
15. Reboot the system

You should now be able to select either WFW311 or WIN98SE and then run WIN to boot the selected operating system.