gg,
Has anyone ever been prosecuted, in the UK, for running an un-licensed Microsoft OS? Because until it is then it is not necessarily enforceable in all cases owing to our law about unreasonable contracts.
I think you would have a hard time trying to prove that Microsoft license agreements were unreasonable.
I personally know of people who have been on the receiving end of a Microsoft audit. No doubt there have been prosecutions somewhere, but I suspect the majority of people agree to become compliant following an audit. Resolving things out-of-court tends to be cheaper for both parties.