It has emerged that a Microsoft scheme offering free upgrades to people buying Vista machines this summer has a maximum limit of 25 machines for businesses, although Microsoft had not stated any limits applied, similar schemes for previous editions of Windows, the deal has been limited to five copies of Windows per customer

The scheme is designed to prevent would-be computer buyers from delaying purchases in the run-up to a new edition of Windows. As well as individuals, the deal is open to small and medium sized businesses.

Larger businesses shouldn’t be affected by the scheme. Firms with more than 250 Windows computers are covered by volume licensing which has separate deals for upgrades.

Meanwhile, in Japan Microsoft’s limited time Windows 7 offer allowing buyers to get the upgrade for Windows 7 Home Premium and Professional at half-price or less if they paid before a certain date appears to be nearing an end with several retailers reporting that they are no longer able to sell the cheap upgrade, suggesting it may have “sold out” in less than two of the ten days allocated by Microsoft to the promotion.

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