A family of Microsoft word processing software products for creating web, email, and print documents.
A contact on the Word team tells me that they are unable to reproduce the problem, but he recalls a similar situation in Publisher (unable to save as PDF) where the problem was that no printer was set as the Windows default. He suggests that you (and others who are having this problem) check to make sure that one of the printers in the list in Word's Print dialog has a green check mark indicating that it is set as the Windows default printer. If not, go to the Printers folder in the Windows Control Panel, right-click one of the printers (if there's no physical printer available, you can select the Microsoft XPS Document Writer), and choose Set as default printer.