www.office.com/setup Blogs: Office 365 is designed to work with the latest version of Office, Office 2013, and Office 2011 for Mac. Previous versions of Office, such as Office 2010 and Office 2007, may work with Office 365 with reduced functionality. Get more details about which Office versions are supported. If you have Office 2003 or an earlier version, you will need to update to a newer version of Office in order to use Office 365; or you can subscribe to one of the many Office 365 plans that include the latest version of Office. In addition to getting the latest version of Office as part of your subscription, you will also get automatic updates, so your Office will always be up to date. Compare plans.
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