Microsoft has unveiled the beta version of an updated desktop virtualisation package, designed to help enterprises migrate to Windows 7 by allowing compatibility with legacy applications that would not otherwise work on the new operating system.

The beta is for version 2.0 of Microsoft Enterprise Desktop Virtualisation (MED-V), which improves upon the existing version 1.0 by simplifying password entry, USB device sharing, and legacy app integration with folders and printers. Version 2.0 also creates more options for running old web apps that require Internet Explorer 6.

MED-V is a bridge to help you create a longer-term plan for your more complex applications that may not be compatible with Windows 7 and are too costly to migrate at this exact moment," Microsoft director of product management Karri Alexion-Tiernan said.

"MED-V can accelerate your migration to Windows 7 by removing legacy application barriers. It delivers a seamless user experience, consolidates legacy desktop hardware and allows users to access the legacy applications from a single desktop experience."

Version 2.0 has been tested with Microsoft's desktop virtualisation technology, App-V, allowing virtualised applications to be "deployed and managed within the MED-V 2.0 Beta workspaces," Microsoft said. Microsoft also focused on improving integration with System Center Configuration Manager.

"MED-V 2.0 workspaces are deployed and managed using existing electronic software distribution (ESD) systems, including System Center Configuration Manager (SCCM) 2007 R2 or higher," Microsoft said.

With the 2.0 beta, users can now cache their password so they don't have to sign in twice. There are several new options allowing IT administrators to redirect legacy Web applications (those that run on IE6 or IE7) to different domains or ports. There is also USB device sharing allowing thumb drives and Smartcard readers to be shared between the host and applications; and integration of legacy applications with the Desktop and My Documents folders, and printers.

MED-V is sold as part of MDOP, the Microsoft Desktop Optimisation Pack. To acquire MDOP, customers must first purchase a Software Assurance subscription, which typically costs about as much as one full Windows licence, essentially doubling the cost of Windows 7. In addition to that, Software Assurance customers must pay another fee per seat per year to obtain MDOP. However, Software Assurance comes with benefits such as upgrades to new software versions, and MDOP itself also includes App-V and several other software tools in addition to the new virtual desktop package.

MED-V isn't the only option for customers looking to solve compatibility problems created by the Windows 7 upgrade. Windows 7 itself includes 'Windows XP Mode', allowing a virtual instance of XP to run on top of the new OS, and virtualisation tools from the likes of Citrix and VMware have been designed to smooth the process of OS upgrades.