Virtual machines that were created on the beta version of the Hyper-V role do not start after the Hyper-V role is updated to a later version

If the virtual machine is running a Hyper-V-supported release version of an operating system, you can use the existing virtual hard disk (.vhd) file. However, the virtual machine configuration settings must be re-created. If the virtual machine is running a prerelease version of Windows Server 2008, the virtual machine configuration settings and the operating system .vhd file must be re-created.

To delete and then re-create the virtual machines, follow these steps.

Step 1: Remove the virtual machines

To remove virtual machines that were created on the beta version of the Hyper-V role, follow these steps:

1. Open the Hyper-V Manager console.
   
2. Document the configuration settings for each virtual machine.
3. Click Delete Save State for each virtual machine that is currently in a Saved state.
4. Click Delete Snapshot Subtree for each virtual machine that has snapshots.
   
   Note As soon as you delete the snapshots, the changes that exist in the snapshot files (.avhd files) will merge into the parent .vhd file. This operation may take a while. To verify that the snapshots have merged into the parent .vhd file, check the location in which the snapshots are stored to verify that no .avhd files exist.
5. On the Action menu, click Virtual Network Manager, and then verify that all virtual networks that were created on the beta version of the Hyper-V role have been deleted.
   
   Note All virtual networks that were created on the beta version of the Hyper-V role will be removed when you update the Hyper-V role to a later version.
6. Copy the .vhd file to a safe location.
   
   Note If the virtual machine is running a prerelease version of Windows Server 2008, the operating system .vhd file must be re-created.
7. In the Hyper-V Manager console, delete all virtual machines that were created on the beta version of the Hyper-V role.
   

Step 2: Re-create the virtual machines

To re-create the virtual machines, follow these steps:

1. Open the Hyper-V Manager console.
   
2. On the Action menu, click Virtual Network Manager, and then re-create your virtual networks.
3. Use the New Virtual Machine Wizard to re-create your virtual machines.
   
   Note If you previously saved a .vhd file that contains a Hyper-V-supported release version of an operating system, you can click
   Use an existing virtual hard disk, and then point to your existing .vhd file. If the virtual machine is running a prerelease version of Windows Server 2008, the operating system .vhd file must be re-created.
4. As soon as the operating system is installed, install the Integration Services in the virtual machine. To install the latest version of the Integration Services, open the Virtual Machine Connection window, and then click Insert Integration Services Setup Disk on the Action menu.