When you try to upgrade to Windows 2000 or Windows XP, you receive:

Microsoft Windows has detected software that is not completely installed on your computer. Windows Setup cannot continue until you finish installing this software.

To finish the installation process for this software quit Windows Setup.
Log off of your computer and then log back on again.
Restart Windows Setup.

When you follow the above instructions, the error occurs again?

To fix this problem:

1. Copy / Paste the following to a DelOnce.reg file:






2. Merge the DelOnce.reg file with your resistry.

NOTE: See An IE install issues a previous program installation was never completed message?