[CPOSharky]

Is there some reason that 90% of my current programs will not work on W10?

[oh8eleven]

Probably a combination of greed and/or MS just couldn't be bothered.
Try this ..."How to Make Old Programs Work on Windows 10"

[rarestia]

You want the technical reason?

I’d guess that if that volume of programs aren’t working, you’re using stuff that’s 10+ years old.

The programming interfaces to the kernel, or the core of the operating system, have changed drastically since XP. Programs can no longer directly address the kernel due to security hardening at all levels of the operating system since the Vista days. It’s only gotten stronger over the years, and Microsoft can now boast a much more secure environment as a result.

If you’re so stubborn that you won’t migrate to newer platforms or upgrade the applications you use, you’d be better off on an off-network, older computer running XP. Do not, under any circumstance, or for any reason, EVER connect an XP machine to the Internet. EVER!