Open Disk Management in the Windows guest, click Action > Attach VHD, browse to the VHD file, and click OK. The VHD must be on a drive already accessible to the VM, such as a VMware Shared Folder or a secondary virtual disk.
Why the VHD file must be visible to mount it
The Attach VHD command in Disk Management only sees files that are already accessible from within the guest operating system. If your VHD file sits on the VMware host’s hard drive but is not shared with the VM, the tool will have no path to it. To make it visible, you have two reliable options. First, you can add a secondary virtual disk to the VM and copy the VHD file onto that disk. The guest then sees it as a local drive letter. Second, you can configure a VMware Shared Folder. In the VM settings, go to Options > Shared Folders, enable it, and map a host folder containing the VHD. The guest will then see that folder under \\vmware-host\Shared Folders. This is the same principle you would follow when you use a VHD in VMware Workstation, ensuring the file is on a path the guest can traverse. For more complex network scenarios, you might first need to setup a network in vmware workstation to get the VHD from a remote server into the guest’s view. For a single file, shared folders are simplest.
Windows guests can mount VHDs natively without converting them to VMDK.
Step-by-step attach process in disk management
Once the VHD is visible inside the guest, launch the disk tool by right-clicking the Start button and selecting “Disk Management.” In the top menu bar, click Action, then select “Attach VHD.” A dialog box appears. Click Browse and navigate to the VHD file’s location. Select the file, and choose whether to make the disk read-only. This is useful if you only need to extract data without risking changes. Click OK. The utility will immediately mount the VHD and assign it a drive letter if the volume inside is formatted and healthy. The new disk appears in the lower pane as a “Disk” entry, usually labeled as “Disk X” with a blue icon indicating a virtual disk. You can now access its contents in File Explorer under the new drive letter. This process works identically whether you originally created the VHD by using a tool to make a VM from your physical machine, or if it came from another source.
When attaching fails or the option is greyed out
If the Attach VHD option in the Action menu is greyed out, the most common cause is that the disk tool does not recognize the file as a valid VHD. This happens when the file is stored on a network share, an external USB drive, or a compressed folder. Windows requires the VHD to reside on a volume that is accessible to the guest. Another reason is that the VHD file is currently in use by another process, such as a backup tool or a previous mount that was not detached. Reboot the guest to clear any locks. If you have a very old guest OS like Windows Vista or Windows XP, native VHD support is absent. You would need to install the Virtual Disk Service update or use a third-party tool. Also, ensure the VHD is not a differencing disk whose parent is missing. If you are trying to use a VMDK file in VMware Workstation, the Attach VHD command will not work for that format. VMDK requires conversion or a different tool, and if you encounter startup issues afterward you may need to fix boot errors after converting VHD to VMDK in VMware. Finally, check that the VHD file is not corrupted. Try opening it with a disk imaging utility to verify its structure before attempting the mount again.
