As if there aren't enough scenarios, Microsoft's does not require a product key: One is baked into the trial. As with the retail versions now available to some users, and that will go on sale Oct. 26, the evaluation automatically activates if the PC has a live online connection.

Microsoft declined to comment when asked to explain the reasoning behind the activation changes to Windows 8. "We have no information to share," a spokeswoman said in an email Monday.

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at , on or subscribe to . His email address is .

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