Microsoft Virtual Server is a scalable server virtualization program distributed by Microsoft that enables multiple operating systems (OSs) to run on a single physical server. The program operates without third-party device drivers and provides isolation between partitions.
Microsoft Virtual Server is commonly used for server consolidation in business networks and data centers. It can also be used by software developers. Version 2005 R2 can support up to 64 guest OSs and employs symmetric multiprocessing (SMP) but does not virtualize it.
In April 2006, Microsoft Virtual Server Enterprise Edition became available as a free download.