Simple hypothetical question for you. I take my laptop containing my North America-only copy of NT on a business trip to London. Upon returning home, I realize what I've unwittingly done. So I call my good friend Bill G. up - we're tight like that, Bill and me - and I explain what happened. "No problem," he says. "We'll let it go - just don't do it again." So, have I violated Microsoft's copyright? Yes or no?
Let's not say London because you can certainly take NT there, say a nasty country. Let's see, you violated the license while there, but the copyright holder orally waived his right to sue for copyright infringement, effectively giving you license after the fact. You're safe.
This license after the fact thing is done all the time by Microsoft. Your company is caught without enough licenses, so Microsoft says it's all good as long as you sign up for a nice long Software Assurance contract that includes licenses and upgrades.