KB2836402 - You cannot add VHD files to Hyper-V virtual machines in Windows Server 2012

Microsoft has posted a knowledge base article about a scenario where VHD or VHDX files cannot be added to Hyper-V virtual machines in Windows Server 2012.

Symptoms

Consider the following scenario:

  • You create some failover cluster nodes on computers that are running Windows Server 2012.
  • You have the Hyper-V server role installed on the cluster nodes.
  • You create virtual machines on one cluster node, and you configure the virtual machines as cluster resources.
  • You create multiple Cluster Shared Volume (CSV) resources and create one Virtual Hard Disk (VHD) file in each CSV.
  • You use Hyper-V Manager to try to add the VHD files to the virtual machines.

In this scenario, you cannot add the VHD files to the virtual machines. Additionally, you receive an error message that resembles the following:

Error applying Hard Drive changes 
‘Virtual machine‘ failed to add resources to ‘virtual machine‘ 
Cannot add ‘C:\ClusterStorage\Volume3\Test3.vhdx‘. The disk is already connected to the virtual machine ‘virtual machine‘. (Virtual machine ID virtual machine ID) 
‘Virtual machine‘ failed to add resources. (Virtual machine ID virtual machine ID) 
Cannot add ‘C:\ClusterStorage\Volume3\Test3.vhdx‘. The disk is already connected to the virtual machine ‘virtual machine‘. (Virtual machine ID virtual machine ID)

Cause

This issue occurs because multiple CSV volumes have the same 0000-0000 serial number. Therefore, the VHD files on different volumes are recognized as the same file.

There is a supported hotfix available from Microsoft.