Applying PS 7.0.1 Updater to NOS legit copy of Photoshop Version 7 for Win - No Go!

Yesterday I recieved from a 100% positive feedback eBay seller what appears to be a completely legitimate new old stock copy of a Photoshop 7 Windows installer on CD-ROM. Spotlessly clean, with an Adobe hologram sticker on the jewel case, another sticker saying "Automatic Activation" and the serial number printed on a sticker on the reverse side. I went ahead and installed PS7 on my new Hewlett Packard HP 250 laptop with 8 gig RAM and 1tb storage running Windows 10 Home Edition without any problems. It seems to be stable and runs real nice and fast. I must point out that I have previously worked with a shrink-wrapped registered copy of PS5.5 for nearly 17 years on a Mac G4 with no trouble at all.

So I downloaded and ran the Photoshop 7.0.1 updater, and got a message saying that it "could not find the Adobe Photoshop 7 folder in the Program Files x86 folder".

Well, it did find the folder, but it would not work - no go, and no show. Another part of the message said " if the installer does not work, then uninstall Photoshop, and reinstall it from the CD-ROM, and then re-run the PS 7.0.1 updater". I dutifully did all this and the same thing happened all over again.

I Googled the problem, and to my amazement found that this is a known issue. Turns out that way back in 2002 Adobe got so fedup with PS7 being pirated that they incorporated a database of known dodgy serial numbers within the PS7.0.1 updater to foil any pirates following the upgrade path by scuppering the update process. Unfortunately, Adobe also included quite a large number of completely legitimate serial numbers, and it may very well be that my copy of Photoshop 7 is one of them!

Could somebody tell me what I need to do to get the updater to work, and is it possible to register a copy of Photoshop now 14 years old? If my copy of Photoshop is legitimate (and I see no reason to think otherwise) can I get a new serial number?