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 , with even more information available .
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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