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Sorry Dave, I’m afraid I can’t do that! PCs refuse to shut down after Microsoft patch
(www.theregister.com)
This is a most excellent place for technology news and articles.
There was a famous bug that made it into 95 and 98, a tick counter that caused the system to crash after about a month. It was in there so long because there were so many other bugs causing stability problems that it wasn't obvious.
I will say that classic MacOS, which is what Apple was doing at the time, was also pretty unstable. Personal computer stability really improved in the early 2000s a lot. Mac OS X came out and Microsoft shifted consumers onto a Windows-NT-based OS.
EDIT:
https://www.cnet.com/culture/windows-may-crash-after-49-7-days/