Most of us are dependent on virtual machines for all kinds of reasons with demos and testing near the top of the list for many of us. Our dependency on virtual machines makes us need better tools for managing them. Windows 7 and Windows Server 2008 R2 can mount a vhd and make it accessible as if it is a mounted drive. The contents of the vhd can be modified without booting up a virtual machine. Under More Actions under Disk Management, is a new option called Attach VHD. It gives you the option to mount a vhd as either read only or modifiable. Curiously, detaching the vhd must be done from a different menu in a different location. The Detach VHD option is found in a menu obtained by right-clicking the square box for the disk in the graphical menu of disk partitions.
Disk Management Showing Attach VHD feature. Detach VHD is from a second screen capture that was superimposed on the first.
Being able to modify the contents of a vhd containing a virtual OS is of particular importance when migrating a virtual machine from Hyper-V to Virtual PC. Although this is a completely unsupported operation, it is something people need to do from time to time. My next post explains how to do this.