> So email uses something called Microsoft Exchange Server, there used to be an on-premises version of this but MS stopped supporting it ...

On-premises Exchange is still supported and licensed. It's a subscription instead of a perpetual license.

> I don’t know if what I said is accurate but know that Exchange server code was like a fossil that didn’t change as much, over the ~5 years I worked on it from 2019-2024.

Exchange is a mature product (albeit not without its flaws). Its era of change was between its 2007 and 2013 versions (inclusive) when it was made more modular and many parts were ported to the .NET runtime. The 2016, 2019, and now Subscription Edition codebases were more of an evolution and has much less churn.

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bigfatkitten 9 hours ago | parent | next [-]

Microsoft will still charge you money for Exchange SE, and occasionally release security and other bug fixes, but “supported” is an extremely generous description of the state of the product.

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EvanAnderson 8 hours ago | parent [-]

Realistically, though, when it comes to support that's every MSFT product unless your org is shelling-out support dollars in advance.

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bigfatkitten 8 hours ago | parent [-]

The difference with their other products is that they generally want you to adopt it, and they actually do feature development, neither of which are true for Exchange SE.

	▲	EvanAnderson 7 hours ago \| parent [-]
		My take is they want anything on-prem to go away. Exchange, in particular, is sort of "feature complete" to me. I'm happy w/ what it does and how it does it for the most part.

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j45 13 hours ago | parent | prev [-]

Exchange should be well protected behind a firewall or 10 after all these years.

What this leaves is a comparison of whether on-premise exchange servers have been compromised or down compared to the cloud.