a) The download versions (for 29.99 euros or 14.99 euros (in recently newly acquired computer)) are generally excluded from the commercial use! The terms and conditions of Microsoft Stores You have to accept where there is in order:
2.2 If you order products via the Microsoft Windows8 Digital Download Store, you warrant that:
2.2.1 [..]; and
2.2.2 not buy this product for business purposes;
b) the maximum number of upgrades to the retail upgrade boxes to 5 pieces per customer (both private and commercial customers) is limited for commercial use. These things I have, however, found only on the FAQ page and not in the license conditions, in so far as it is questionable to what extent this is actually legally effective.
