Customers must redeem the free offer no later than May 31, 2013.
Details about the upgrade offer, including a full list of eligible versions of Office 2010 and Office for Mac 2011, can be found on this Microsoft website, with even more information available on the offer's terms page.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed. His email address is email@example.com.
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