With respect to the registry errors, I'm not sure, but it sounds like you began at the beginning of the article. That was not actually what I wanted you to do. If you didn't start at Using System.da0, then I would try again, following exactly my instructions here:
1 -- boot to a command prompt by tapping f8 on startup, then selecting "command prompt" from the startup menu.
2 -- at the c:\> prompt enter: cd: c:\windows (now you should be at c:\windows\>
3 -- enter attrib -h -r -s system.dat
4 -- enter ren system.dat system.bad
(note the position of spaces designated by ^ here: attrib^-h^-r^-s^system.dat; ren^system.dat^system.bad)
>> Do you get an error message entering either of the above two commands?
5 -- ctrl-alt-del to reboot
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When you unzip the zipped boot disk setup file, you must remove it from the original zipped folder, this is either done automatically by the zip program or you can simply manually copy the enclosed file to another folder. Once you have it out, put a clean floppy in the floppy drive and just double click the setup program and follow the prompts.
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You might also want to double check on finding the ProductKey again, I'm rather concerned that if you try to reinstall, you will receive a Microsoft prompt for that (the number of characters is different) and it will not accept the ProductID, which was placed there by the orginal vendor, not Microsoft.
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If only the ProductID is there, I would recommend trying to reinstall from the cab files on the hard drive first, if they are present. To determine that, from a command prompt enter:
cd c:\windows\options\cabs
If you get the DOS prompt c:\windows\options\cabs\> after that, then you have them. From that directory, it might be possible simply to enter:
setup and follow the prompts.