Office 365 works best with the latest versions of Office: Office 2010, Office 2013, Mac. oOffice 365 works with a slightly limited functionality with office 2007. If you have an earlier edition of office, 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 receiving the latest version of office as part of your subscription, you will also receive automatic updates, so your Office will always be up to date.