Microsoft Virtual Server was a virtualization solution that facilitated the creation of virtual machines on the Windows XP, Windows Vista and Windows Server 2003 operating systems. Originally developed by Connectix, it was acquired by Microsoft prior to release. Virtual PC is Microsoft's related desktop virtualization software package. Virtual machines are created and managed through a Web-based interface that relies on Internet Information Services (IIS) or through a Windows client application tool called VMRCplus. Virtual Server has been discontinued and replaced by Hyper-V.