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Update enables downgrade rights between Windows 10 IoT and Windows Embedded 8.1 Industry
Content provided by Microsoft
Applies to: Windows Embedded 8.1 Industry Enterprise, Windows Embedded 8.1 Industry Pro
This article describes an update that enables downgrade rights between Windows 10 Internet of Things (IoT) and Windows Embedded 8.1 Industry. Before you install this update, see the Prerequisites section.
About this update
The operating system is not activated when it downgrades from Windows 10 IoT to Windows Embedded 8.1 Industry. This update provides the required Product Keys that bridges Windows 10 IoT Enterprise and Windows Embedded 8.1 Industry. The change is made to the Windows Embedded 8.1 license file to accept the Product Keys that has been issued to the Windows 10 IoT Enterprise edition.
How to get this update
Important If you install a language pack after you install this update, you must reinstall this update. Therefore, we recommend that you install any language packs that you need before you install this update. For more information, see Add language packs to Windows.
To apply this update, you don't have to make any changes to the registry.
You may have to restart the computer after you apply this update.
Update replacement information
This update doesn't replace a previously released update.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Microsoft has traditionally provided downgrade rights to original equipment manufacturers (OEMs) for certain versions of Windows. This is when the OEM purchases a set of Product Keys for version x but installs version x-1 for some time after version x launches. The product key works for both versions.
Note The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed in the "Additional file information" section. MUM, MANIFEST, and the associated security catalog (.cat) files, are very important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.