OpenNT: A Fork of the Microsoft Windows NT 4

This is based on the leaked Nt4 source code with some changes merged from W2K hence the 4.5 moniker.

I expect the code would be fun to read. It leaked out of Israel (I think) about a decade back and if I remember correctly the entire NT4 tree leaked plus significant components from 2k.

Can't imagine Microsoft will be too happy with this.

There is something seriously wrong with your IT infrastructure if it's easier to create a clone of an ancient operating system then it is to upgrade the software you are running to newer OSes. There is something seriously wrong with your corporate infrastructure if those upgrades weren't just happening as a matter of course over the years. "A stitch in time saves nine."