Allchin, then the Microsoft Windows chief, sent this self-described "rant" to Gates and Microsoft CEO Steve Ballmer in the midst of the company's work on Longhorn, the code name for the operating system that would become Windows Vista. The message, with the subject line, "losing our way," outlined Allchin's frustrations at the time:

I am not sure how the company lost sight of what matters to our customers (both business and home) the most, but in my view we lost our way. I think our teams lost sight of what bug-free means, what resilience means, what full scenarios mean, what security means, what performance means, how important current applications are, and really understanding what the most important problems [our] customers face are. I see lots of random features and some great vision, but that doesn't translate onto great products.

I would buy a Mac today if I was not working at Microsoft.

The message was disclosed during the company's Iowa antitrust trial. After it surfaced, Allchin said he was "being purposefully dramatic in order to drive home a point," and that the development process was dramatically changed after he sent the message.

Honorable mention goes to another Allchin e-mail that surfaced during the Iowa trial, with the provocative subject line, "sucking on media players." Read it and the ensuing exchange here: PDF, 2 pages.

Raikes, who plans to retire from the company later this year, sent this e-mail to the iconic investor as an academic exercise, of sorts -- outlining Microsoft's business strategy in an effort to demonstrate to Buffett the value of the company as an investment. Among other things, Raikes highlighted the dominant market position of Windows and described the "pricing discretion" that Microsoft has been able to exercise.

"In some respects I see the business characteristics of Coca Cola or See's Candy as being very similar to Microsoft," Raikes wrote, referring to two of Buffett's high-profile investments. "E.g. in FY96 there were 50 million PC's sold in the world, and about 80% of them were licensed for a Microsoft operating system. Although I would never write down the analogy of a 'toll bridge,' people outside our company might describe this business in that way."

Raikes added later, "There is an R&D charge to the business, but I'm sure the profits are probably as good as the syrup business!"

The message didn't turn Buffett into a big tech investor, but it was helpful to plaintiffs pursuing the company on antitrust charges. It surfaced years later as evidence in a class-action suit against Microsoft in Minnesota.

This was the first in a series of leaked Microsoft memos received by open-source guru Eric S. Raymond. They're known as the "Halloween" documents because that's when the first of them surfaced.

The memo is notable in part because it marked Microsoft's rising awareness of open-source software, such as the Linux operating system, developed by a worldwide community of programmers. It also showed how the company was thinking about protecting its business from Linux, with bullet points including, "Fold extended functionality into commodity protocols / services and create new protocols."

In an online response at the time, Microsoft said the documents "do not represent an official Microsoft position or road map," describing them as "technical analyses written by a staff engineer that represent the thoughts of one individual at one point in time."

Made public this week, these e-mails reveal the behind-the-scenes deliberations over the "Windows Vista Capable" designation, suggesting that Microsoft lowered the standards for that classification to appease Intel, over the objections of some Microsoft executives and others in the industry. The messages also illustrate the problems that some Microsoft executives experienced with Windows Vista on their own computers.

"We need to be clearer with industry and we need to decide what we will do and do that well and 100% and not just do a little of everything which leaves the [Independent Hardware Vendors] in a confused state," wrote Steven Sinofsky, the new Microsoft Windows chief, in a February 2007 e-mail made public as part of the batch.

Those documents were produced while the plaintiffs in the Windows Vista case were seeking class action status. Now that the suit has been granted that status, the plaintiffs' lawyers are expected to seek additional documents as the case proceeds toward trial.

This message differs from the others in that Microsoft itself now makes it available for historical reference, but it's clear that Gates meant it for an internal audience at the time. Sent to executives including Raikes and Ballmer, it's notable because it marks the moment when the Microsoft co-founder recognized the company's rise to the top spot in the industry.

The full text:

As conservative as we are about self-congratulations and celebrating our achievements, I have to say, as today went on, I got pretty excited about the fact that we are now the number 1 software company in every respect (sales, profit, units, leadership, people...) In fact when I think of Lotus's statement at the introduction of their annual report where they say "there is increasing evidence that LOTUS is the preferred vendor, the preferred investor and the preferred employer," I think they are kidding themselves. We didn't just have somewhat higher sales that they did – we had $14M more in sales which puts us ahead for 3, 6, 9 and 12 months (I think). Of course their sales may go past ours again and it's not really our goal to be #1, but I do get a real kick out of the (fact) that their big distraction of being the largest is being taken away BEFORE WE HAVE EVEN BEGUN TO REALLY COMPETE WITH THEM. Actually, I found out these numbers about 5pm, so I've been enjoying it for only 6 hours and it will be a fact of no importance in a few days but I think it's really great.

For the record, this list doesn't include some key Microsoft memos, such as Bill Gates' "Internet Tidal Wave" (PDF) and "Trustworthy Computing" e-mails, that were widely published as a means of communicating with the industry and the public.

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