It has been an ongoing sore spot for Microsoft that its highly trafficked Hotmail site runs atop not its own operating system, but the FreeBSD-Apache platform. Since it bought Hotmail at the end of 1997, Microsoft repeatedly promised that it would transition Hotmail to Windows NT, then Windows 2000. More than anything, Microsoft's desire was a matter of personal pride. What better way to prove its own contention that NT was just as scalable and robust as Unix than to run its complex, free, Web-based email infrastructure on it. According to the market watchers at Netcraft -- an Internet consultancy based in Bath in the UK -- Microsoft finally has commenced the long-awaited Hotmail migration. At present, five to ten percent of Hotmail requests are being served by Windows 2000, according to Netcraft. The remaining percentage are still served off FreeBSD-Apache. "The Hotmail site infrastructure is enormous, and even if everything runs smoothly, a migration will likely take several weeks," Netcraft researchers said. As of February 2000, Microsoft claimed it had 30 million Hotmail users worldwide. Will moving to Windows 2000 play havoc with Hotmail subscribers' accounts? Microsoft officials confirmed that the conversion is underway -- and will likely be finished by this autumn. But officials did not respond to other Hotmail-related questions. But Hotmail users have been plagued in the past by a variety of problems, including security breaches, lost address books and missing email messages. Users have complained of losing access to their accounts while Microsoft was performing routine maintenance on the Hotmail site. Hotmail is one of several Microsoft MSN services. Like Passport, Microsoft's Internet authentication service, Hotmail will likely be one of the first of the Microsoft .Net services that the company will provide to developers and users as part of its software-as-a-service vision. Hotmail already is an integrated component of many of Microsoft's other products and sites. Hotmail already is integrated with Microsoft's MSN Messenger instant messaging software, as well as with its Outlook Express 5.5 client. The next version of Microsoft's MSN, available in beta as MSN Preview 1, integrates Hotmail into the core Web-browsing software. Windows Millennium Edition, the consumer version of Windows due to ship this fall, integrates Hotmail into the base operating system. Hotmail isn't the only Microsoft application that is hosted on a non-Microsoft operating system, according to Netcraft. "LinkExchange, the other prominent FreeBSD site owned by Microsoft, still runs FreeBSD but redirects users to bCentral," Netcraft reported. LinkExchange is Microsoft's online marketing services property, which the company acquired in November 1998. Microsoft's decision to move Hotmail from Apache to its own Internet Information Server Web server represents a shift from the number one Web server platform to the number two choice in the market. The Apache open source server remains the runaway best seller among Web servers, with an estimated 63 percent of the market, according to the Netcraft Web server survey. Microsoft's Internet Information Server (a component built into Windows NT and Windows 2000) is second with 20 percent, and Netscape/i-Planet is third with seven percent. But there are numerous other Web servers including WebLogic, Zeus and RapidSite. And the growth of Web and application hosting is providing companies that sell Web servers with a fertile, booming customer base. What do you think? Tell the Mailroom. And read what others have said.