Source: http://www.rt7lite.com/rt-se7en-lite-forum/6-unattented-installation-support/1111-invalid-product-key.html


Invalid Product Key 2 Years, 4 Months ago Karma: 0
I created an unattended disk with rt seven lite, but when I go to install it, it tells me the windows product key is invalid. I know it is valid because I have windows 7 installed already. I also created a disk with rt seven lite that didn't have unattended installation and it activated just fine. Any help?

SOLUTION:


Re:Invalid Product Key 2 Years, 2 Months ago Karma: 0
This error occurs if you have specified a Volume License Multiple Activation Key (MAK). When you install Windows with the MAK, it must be specified with the ProductKey setting in the Microsoft-Windows-Shell-Setup component.
However, RT Se7en Lite only specified the product key in Microsoft-Windows-Setup|UserData|ProductKey in the unattend file.

To resolve this issue Open Autounattend.xml, Go under line 80 (<component name="Microsoft-Windows-Shell-Setup" .. >) and Type: 
<ProductKey>xxxxx-xxxxx-xxxxx-xxxxx-xxxxx</ProductKey>

Go to line 28 and remove lines 28,29,30, and 31
<ProductKey>
<Key> xxxxx-xxxxx-xxxxx-xxxxx-xxxxx </Key>
<WillShowUI>OnError</WillShowUI>
</ProductKey>
Michael Feldman 
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