Disabling the Windows Update feature avoids some I/O operations to the file system and can reduce the growth of an instant clone's or a linked clone's virtual disk.

Evaluate the needs of your environment before disabling Windows Update. If you disable this feature, you can manually download the updates to the parent or master image virtual machine and then use the push-image operation for instant clones or recompose for linked clones to apply the updates to all the clones.

The following steps apply to Windows 7 and Windows 8. The steps might vary on different Windows operating systems.


  1. In vSphere Client, select the parent virtual machine and select Open Console.
  2. Log in as an administrator.
  3. Click Start > Control Panel > System and Security > Turn automatic updating on or off.
  4. In the Important updates menu, select Never check for updates.
  5. Deselect Give me recommended updates the same way I receive important updates.
  6. Deselect Allow all users to install updates on this computer and click OK.