Microsoft has announced pricing and licensing details for Windows Server 2008, its long-awaited server product due for release in February, and revealed that the commercial name for its virtualisation product will be Hyper-V, formerly known as Viridian. The announcements came on the first day of IT Forum, its largest customer conference in Europe.

On its website, Microsoft is billing the official launch of Windows Server 2008, which will take place in Los Angeles on February 27, as "the most important enterprise launch in company history". That launch will also showcase Visual Studio 2008, the company's application development tools, and SQL Server 2008, its database.

Windows Server 2008, formerly known as Longhorn, has been delayed several times, but since September some customers have been testing the release candidate, the term for when software is in its final stage of refinement before release.

The company is vowing no more delays: Microsoft is "absolutely on schedule" for the launch of Windows Server 2008 in February, said Andrew Lees, corporate vice president for server tools and marketing, on Friday.

Microsoft will release five versions of Windows Server in February, Lees said: Standard, Enterprise, Datacenter, Web Server and a version for Itanium-based systems.

Within six months of the Windows Server 2008 launch, it will also release Standard, Enterprise and Datacenter versions incorporating its Hyper-V virtualisation software.

Virtualisation enables one physical server to host several operating systems, which can be assigned to run certain applications. It means one physical server can be worked harder, often reducing the need for more server hardware, which in turn bring benefits such as lower power bills for data centres.

It's complicated technology, however, both for management and security, and only about five percent or less enterprises are now actively using virtualisation. However, the market for virtualisation products is expected to grow rapidly over the next few years, according to market analyst IDC.

Virtualisation also means that enterprises can opt to run more copies of free OSes, such as Linux. "Virtualisation poses a substantial risk to Microsoft, since the benefits of free alternatives, such as Linux OSes, Apache for web serving and MySQL for database are enhanced when customers begin running multiple instances of them on each devices," according to a May report by analyst Directions on Microsoft.

Microsoft is trying to build excitement around its virtualisation product to catch VMware, a subsidiary of EMC, which leads the market by a wide margin. Microsoft will try to best VMware by providing management tools that allow, for example, an administrator to quickly deploy another virtual server if one is backlogged with tasks, Lees said. Microsoft's virtualisation tools will also allow a view into how the OSes and applications are performing and allow modifications, he said.

"We will provide a more comprehensive strategy around how to manage and utilise server deployment in terms of the server virtualization and management of that data center," Lees said.