This question is the opposite of the problem that most people have, and I haven't found a good answer for it yet.
My company has custom hardware configurations on shipped systems, and we are currently still using Windows 7 for our O/S (for the time being).
However, in our license acquisition from Microsoft we are now getting Windows 10 keys. Previously, we could use Windows 8 or 8.1 keys to activate Windows 7, but the new Windows 10 keys seem to have an incompatible format.
Does anyone know how we can use our Windows 10 keys to activate our Windows 7 installations?
31 Answer
According to Microsoft, you can't use your Windows 10 keys. You will have to call Activation Support, provide proof that you have a license with downgrade rights, and they will provide a response to the activation challenge that will result in a one-time activation of an install.
The downgrade process
Follow these steps to downgrade to an earlier version of Windows software:
- Use genuine Windows media and a corresponding product key for the version of Windows that is eligible for downgrade. The media/key should come from a previously licensed product from the OEM or retail channel.
- End users who are licensed separately through Microsoft Volume Licensing (VL) may provide their VL media and key to a system builder to facilitate the downgrade on their own systems.
- Insert the downgrade-eligible version of Windows media and follow the installation instructions.
- Enter the product key.
- If the software was previously activated, it cannot be activated online. In this case, the appropriate local Activation Support phone number will be displayed. Call the number and explain the circumstances. When it is determined that the end user has an eligible Windows license, the customer service representative will provide a single-use activation code to activate the software. Please note that Microsoft does not provide a full product key in this scenario.
- Activate the software.
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