"Build 97241 contains a potentially fatal bug that could wipe your computer. If you are using Build 97241, please upgrade it to a more recent build or otherwise cease using this build immediately. We do not care how you acquired this build. We simply do not want you bricking your computer."
customer: I'm trying print and it just says "error"
me: It just says error?
customer: yes
me: Are there any other words or error numbers?
customer: yeah, it says "No printers are installed. Add a printer and try again"
me: facepalm
Their solution works because it communicates a lot while saying very little
I imagine in Windows' case, some enterprising individuals who don't know better will end up installing these builds on various computers, and you end up with a large group of users on the wrong build who:
1. Expect better quality than the pre-release build provides.
2. Blame Microsoft for their pre-release build breaking.
Raymond Chen also mentions a third case where the pre-release build messes up other parts of the network... so now you've got:
3. Somebody else blaming this guy for something he genuinely thinks is Microsoft's fault.
And then if you put out a warning message, it's typically ignored because the software is 99% working until catastrophic failure. And then you still get blamed by unreasonable users who then spread the word about how much you suck but conveniently leave out the "leaked pre-release build" part of the story. (If you sense some bitterness, yeah, I've had a few of my own experiences with much less consequential software.)
It's a lose-lose situation for Microsoft. I don't envy anybody in that position, regardless of the quality of the final finished product.
Even if it was today and such a note was published on the Internet, do you think that people who use leaked builds--in at least semi-production settings even--would see that note, much less actively seek it out?