Original Equipment Manufacturer (OEM) licenses are provided through computer manufacturers such as Dell or Lenovo. This licensing scheme typically ties the hardware configuration of a machine to its Windows product key.
Since a machine virtualized on a Datto device is using virtualized hardware provided by a hypervisor, the OEM license may no longer be recognized as valid.
Restoring to different hardware from a backup may also cause Windows to prompt you for re-activation for the same reason.
To obtain a temporary or permanent license activation for restored machines, you must call the manufacturer or other provider of the OEM license. Datto is unable to support third-party licensing issues.
Microsoft's article discussing the transfers of OEM licenses can be found here.
Note that Microsoft Windows XP and Server 2003 are officially not supported by Microsoft.
StorageCraft's article can be found here: Windows OEM Licenses and HIR or Virtual Boot.
Additional information regarding preserving OEM pre-activations is available in the following Microsoft TechNet articles:
- Preserving OEM Pre-Activation when Re-installing Windows XP
- Preserving OEM Pre-Activation when Re-installing Windows Server 2003 R2
- KMS Client Setup Keys for Windows 10, Windows 8.1, and Windows Server 2012 R2