In its biggest release of the year, Microsoft launches new versions of its server operating system and database software later today, aiming to crack the Unix dominated high-end market and boost .Net web services adoption.

Windows Server 2003, SQL Server Enterprise Edition 2000 64-bit and Visual Studio.Net 2003 will be unveiled this afternoon at a worldwide launch hosted by Microsoft chief executive Steve Ballmer.

Early customers include passenger transport and leisure services firm Sea Containers, which is implementing an Active Directory-based upgrade from multiple NT4 domains as part of an IT infrastructure overhaul.

"The opportunity to move to a much more flexible single environment is more appealing," Duncan Scott, vice president of information services at Sea Containers, told vnunet.com.

"We saw Windows Server 2003 as a much better hook into the whole .Net world."

The London Stock Exchange (LSE) is using Windows Server 2003 as a platform for new revenue-generating financial data services.

"A key requirement for all of the LSE's new value-add real-time market data products is that we are able to calculate and deliver market information to our customers faster than they can do it themselves," said Mathew Wootton, information product development manager at the exchange.

And vnunet.com can also reveal that high street retail chain House of Fraser is to sign a deal for Windows Server 2003 as the basis for a new multi-channel customer ordering system later this year.

"We are looking at implementing a new customer ordering system that will eventually be multi-channel covering kiosks, the web and even the call centre environment, and it does need some of the features of Windows Server 2003," said Frank Berridge, IT director at House of Fraser.

Analysts indicated that Windows Server 2003 is a significant improvement to NT4 and Windows 2000.

"This platform represents a sharp improvement in quality, reliability and security for Microsoft," said Rob Enderle, research director at Giga Information Group.

Some analysts have questioned whether this will be enough to dent the high-end Unix market, but Gordon Smillie, group director of the Enterprise and Partner Group at Microsoft, insisted that Windows is now ready to compete in the data centre.

"This is the first release since the announcement of our Trustworthy Computing initiative and takes to new levels the security, reliability and availability of Windows," he said.