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If some users in your organization are Excel expert users who work with complex Excel spreadsheets, they can install the 64-bit edition of Office 2013 to move beyond the 2 GB addressable memory boundary that is imposed on 32-bit editions. Note that this boundary differs from the physical (on disk) size of the spreadsheet on your computer's hard disk drive. It is possible to have an Excel file whose size on disk is smaller than 2 GB, but which when it is opened contains enough data to occupy 2 GB or more of addressable memory.