Microsoft Virtual Hard Disk (VHD) format is a common virtualization file format that is used by virtualization solutions from Microsoft, i.e. Hyper-V and Virtual PC. Through VHD, Microsoft allows customers easily test drive and evaluation Microsoft and partner products or solutions by using virtual machines.

The concept of VHD is pretty much the same with VMWare virtual appliances which is fully pre-installed and pre-configured application and operating system environment that allows user to immediately run the system in a virtual machine or ‘black box’, eliminating the need for installation, configuration and maintenance costs associated with running complex stacks of software. With VHD, Microsoft aims to provide a uniform product support system, and more seamless manageability, security, reliability and cost-efficiency for customers.

All Virtual Hard Disk is available for free download, and is subjected to 30-day open evaluation time period. VHDs only run on Microsoft Virtual Server 2005 R2 software, which users need to download and install.

Currently the following Microsoft server products are available in VHD format:

Windows Server 2003 R2 VHD
Exchange Server 2007 VHD
ISA Server 2006 VHD
SQL Server 2005 VHD

Download the VHDs from VHD Download Center.