Is it possible (and safe) to copy the SoftwareDistribution\Download folder from one Windows XP machine, A, to another, B, and then let update.microsoft.com do its thing on B minus the download time for all packages that have been downloaded on A?
Are other files and/or directories required to make B accept/check the copied files?
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I doubt the feasibility of your idea.
Unless the software installed among two machines are exactly the same, the contents of the \Download folder should be different, not mentioning different hardware configurations. I am not sure whether Windows is adding any machine specific encoding for the \Download folders.
If your goal was to minimize Internet traffic on downloading Windows updates, and if you have a Windows server in your network, you should use WSUS to distribute updates.
I've done this before.. The problem is that copying only this folder won't do anything. What is more this technique (if you can say so) is extremely dirty.
During the update, windows firstly downloads some files, then extracts and lastly deletes some of the downloads. You need to catch the moment when windows has downloaded all the files, and didn't start updating. If you start copying after finished update, those files will be no use for you.
