In some cases you must activate Windows when you create, import, or migrate a virtual machine.

When you install Windows on a computer, you must activate it to use it. You activate Windows either over the Internet or by phone with Microsoft Support. When the Windows operating system starts up, it checks to see if it is running on the same hardware on which it was originally installed. If the hardware has changed, the Windows operating system requires reactivation.

If you install Windows as a guest operating system in a new virtual machine, it requires activation the same as if you had installed it on a physical computer. If you import a virtual machine from another source, if you run the Boot Camp partition as a virtual machine, or if you migrate a physical PC to a virtual machine, Windows recognizes that the virtual hardware is different.

The type of license you have for your Windows operating system can affect how you activate Windows after you start to use it in a Fusion virtual machine.

  • With an OEM license, Windows is tied directly to the hardware on which it was loaded by the manufacturer. Most pre-installed versions of Windows have OEM licenses. OEM licenses generally cannot be transferred to another computer, or to a virtual machine. If you use the Fusion Migrate Your PC feature to migrate one of these types of systems to a virtual machine, you might be required to purchase a second license (or product key) from Microsoft. If a second product key is required, you can get that through the Microsoft representative when you call Microsoft Support to activate the operating system now residing in the virtual machine.
  • With a retail license, when you buy Windows from a vendor, the license enables you to change platforms as often as you want. In this case, you can reactivate Windows over the Internet, or by phone with Microsoft Support.
  • With an enterprise license, you can move the operating system around freely.


Install VMware Tools in the virtual machine before you activate Windows. VMware Tools keeps track of the activation keys. Without VMware Tools installed, you must reactivate Windows each time you start up the virtual machine.


  • Activate Windows online or by phone.
    The Help and Support item on the Windows Start menu enables you to find specific information about activation for that version of the operating system.

What to do next

If you have activation questions, contact Microsoft.