I'm not sure that you are actually referring to the "Classic" (System 9.x running under OS X) or
whether you are referring to System 9.x running on its own.
I suspect that what you are asking is related to OS X and not to Classic. If this is the case, then take a look at this that I found on-line:
Reboot
Hold apple + s down after you hear the chime.
When you get text prompt enter in these terminal commands to create a brand new admin account (hitting return after each line):
mount -uw /
rm /var/db/.AppleSetupDone
shutdown -h now
After rebooting you should have a brand new admin account. When you login as the new admin you can simply delete the old one and you're good to go again!
Is that what you meant?
BTW, upgrade discs are usually CD/DVD which are always locked to Read Only
P
Greetings:
Back in December '13 I asked what to do when you install an upgrade disk that you discover is locked. I wanted to know if it was possible to go back. I was referred me to a post where someone gave instructions on "tricking" your computer into thinking it was new, fresh out of the box. At the same time, the old data and files would be untouched. It involved writing code--and it worked. There were a lot of people responding and thanking the writer for this "miraculous" advice--including me. Now I can't find that file (I printed the instructions out) nor can I find my response. If I could, I would be able to locate the original instructions. Can anyone help?

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