Thanks for the question Rob. I think I need a little more info to answer you correctly.
Are you intending to deactivate windows on some machines so you can use them on others? If so, that's actually not how MSDN works. MSDN licenses *you* to use the software, it doesn't license a certain number of machines or number of installations or copies or anything. If you're licensed, and you're following the terms of the license (i.e. development and test use only), then the MSDN license covers you and you dont need to shuffle software around in order to stay licensed. Each key in MSDN has multiple activations on it, so you can use the same key in multiple machines. So unless you individually are installing windows on many many machines, you'll be fine with an MSDN license. If you run into a limit, you can contact MSDN Subscriptions Customer Service and request more keys for your use.
Does this help answer your question? or if not, can you help me understand what you're trying to do with the deactivation? and why you think having all of your test boxes covered under MSDN wouldn't work for you?
Thanks,
Mike
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