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On the same computer, the bitness of Outlook depends on the bitness of the Windows operating system (x86 or 圆4), and of Microsoft Office, if Office is already installed on that computer.
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Starting in Microsoft Office 2010, Outlook is available as a 32-bit and a 64-bit application. In this topic, bitness is used to qualify the version of Windows, Microsoft Office, Outlook, or a MAPI application built to suit a 32-bit or 64-bit processor architecture of a computer, and possibly other applications that run on that computer.
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The term bitness refers to the distinction between 32-bit and 64-bit processor architectures and the associated compatibility of applications.
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