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  SU0168 Error (OSR2 Issues)

I am trying to install Windows 95b (OSR2) over an earlier version of Windows 95. I am getting an "SU0168" error message that says I already have an operating system.
This article discusses upgrading from Windows 95 or 95a to Windows 95b.

If you are upgrading from Windows 95 or 95a to Windows 98 or ME go to:
     SU0168 Error (Upgrading Over Win95)

If you are upgrading from Windows 3.1x to Windows 95/98/ME, see:
     SU0168 Error (Upgrading Win3.1x)

Windows 95b (also called OEM Service Release 2 or OSR2) is an "OEM" distribution designed to be installed only on new systems. Unlike the "upgrade" releases usually sold in retail outlets, OSR2 is designed not to upgrade an existing Windows installation. However, it is possible to "fool" the setup program into performing an upgrade.

Attempting to upgrade Windows 95 or 95a to OSR2 is risky. I do not recommend it. You have been warned! If you screw up your system, I don't want to hear about it. If you feel that you must try this, read the Computer Clinic's
Windows 95 OSR2 FAQ first -- specifically, the section on upgrading to OSR2. It is a good discussion of the perils involved in trying to use OSR2 as an "upgrade" distribution.

There are at least four techniques for doing an upgrade with an OEM Windows distribution. 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 methods.

Method #1:
Not Recommended
This technique involves launching Windows setup from within the current version of Windows, 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 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 files.
Method #4:
This is similar to method #3. You don't need to rename any files but do need an OSR2 "Startup Disk."

Reference: Search of Usenet database and user feedback.


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