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  SU0168 Error (Upgrading Win3.1x)

I am trying to install Windows 95 (or 98 or ME) over Windows 3.1. I am getting an "SU0168" error message that says I already have an operating system.
This article discusses upgrading from Windows 3.1x to Windows 9x/ME. If you are upgrading a different version of Windows, you are in the wrong place!

If you are upgrading from Windows 95 or 95a to Windows 95b (OSR2) go to:
     SU0168 Error (OSR2 Issues)
     It is very important that you read this article!

If you are upgrading over an older version of Windows 95 with Windows 95a or Windows 98 or Windows ME, see:
     SU0168 Error (Upgrading Over Win95)

You've probably acquired a "full" or "OEM" Windows distribution. Unlike the "upgrade" release usually sold in retail outlets, this version is designed not to upgrade an existing Windows 3.1x installation to Windows 9x/ME. However, it is possible to "fool" the setup program into performing an upgrade. There are at least four techniques purported to accomplish this. I've summarized them below. Click on the links to obtain the full description.

Note! Based on user feedback, 
method #3 works best. Method #4 also works and is handy under special circumstances. Unless you are just curious, don't bother trying the other techniques.

Method #1:
Not Recommended
This technique involves launching Windows 9x/ME setup from within Windows 3.1x, interrupting installation after the dialog that generates the "SU0168" error, editing one of the temporary configuration files and then restarting the process.
Method #2:
Not Recommended
This approach is similar to method #1, but interrupts Windows 9x/ME setup at a different point.
Method #3:
This is by far the simplest approach and is the one most likely to succeed. It avoids the "SU0168" error message by renaming certain Windows 3.1x files.
Method #4:
This is similar to method #3. You don't need to rename any files but do need a Windows 9x/ME "Startup Disk."

Reference: Search of Usenet database and user feedback.


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Copyright © 1997-2001 by William K. Walker
Last update: 19 March 2001