I just ran into a weird situation where the answer files I've been using since Vista time were not working on a Windows 10 Pro 1709 DVD I just got. It made no sense really so I had to do a WSIM validation and it just said the setting did not exist. The one it was complaining about was ProductKey/Key but it was not obvious. I deleted the object in WSIM and re-added it, then compared the old vs new XML that WSIM liked.

The difference was an uppercase K. For years this worked and worked fine:

                <ProductKey>
		    <key>XXXXX-XXXXX-XXXXX-XXXXX-XXXXX-XXXXX</key>
                    <WillShowUI>OnError</WillShowUI>
                </ProductKey>

But against the Windows 10 1709 catalog, it doesn't. It only recognizes Key and not key. And of course this isn't documented anywhere online that suddenly this one XML object is case sensitive. What a thing to change!

Just checked my win 7 which was made from a previous Vista xml & was all uppercase, my modified win 7 one used for current win 10 is same.

Quote

<ProductKey>
                    <WillShowUI>Never</WillShowUI>
                    <Key></Key>
                </ProductKey>

 

I think that it doesn't matter for the old OSes. As I said, I have just been using the same XML I made in WSIM for Vista on every OS since then, and they all have the lowercase k in key and it was starting this version that it would accept it. It is not a wholesale change as you can still use lowercase for other objects like settings, component, unattend and cpi. It isn't something enforced by the schema either, it would have been a problem if it was like <key></Key> but the case doesn't matter in XML as long as it matches.

I sounds a lot like a good example of Chesterton's Fence

https://en.wikipedia.org/wiki/Wikipedia:Chesterton's_fence

jaclaz