Microsoft will this autumn finally address the embarrassing fact that its Hotmail email service is not running on Windows servers.

Hotmail users have been promised a superior service once Microsoft completes the migration of the service from open source technology to Windows 2000 this autumn.

Shereen Meharg, marketing communications manager at MSN, said Hotmail's infrastructure would be moved from Apache Web servers on FreeBSD to Internet Information Server on Windows 2000 by autumn this year.

"The move to Windows 2000 servers will be seamless and the 67 million Hotmail users will not be inconvenienced," said Meharg. "We'll get better efficiency with Windows 2000 than with FreeBSD and we'll be able to expand services."

Among the new services expected are a Microsoft Office spellchecker and better internationalisation tools. Existing facilities such as antivirus scanning and spam blocking will be retained, although it is unclear whether these will be Windows 2000 versions of existing applications or sourced from different suppliers.

Hotmail running on open source technology has been a continuous embarrassment for Microsoft since it bought the service in December 1997. This discomfort has been only been intensified as the software giant's strategy has shifted to the delivery of services over the internet.

Reliable reports suggest that Microsoft has been trying to move the service on to Windows NT since 1998 but has run up against scalability issues. Now, it seems, Windows' time has come.

"With Windows 2000 the time has come to migrate. We're confident that Hotmail will have better uptime after the move," said Meharg, who added that Microsoft also hopes to reduce development costs by using Windows 2000.

Internet consultant Netcraft reports that some Windows 2000 machines have recently been moved into the load balancing pool, with currently between 90 and 95 per cent of requests being served by the established FreeBSD/Apache platform, and five to 10 per cent from Windows 2000.

Nathan Gilks, technical services manager at PSINet, an ISP that is heavily involved in hosting the servers of companies providing services over the internet, said it is still evaluating Windows 2000.

PSINet offers hosting on servers running Windows NT4, Linux and Solaris, and finds that its Microsoft servers have more downtime. However, Gilks stressed that this is not the only consideration.

"There are pros and cons to using either Linux or Windows for hosting. With Windows there are a lot of applications available, but Linux is free, and open source code can be tailored to suit our customers," he said.