Microsoft Office includes the ability to roam settings for specific Office features amongst devices by storing this data ...

Microsoft Office includes the ability to roam settings for specific Office features amongst devices by storing this data in the cloud. This data includes user activity such as the list of most recently used documents as well as user preferences such as the Office theme. This policy setting controls whether this data is allowed to be stored in the cloud. If you enable this policy setting, roaming settings are only stored locally and not synchronized to the Microsoft Office roaming settings web service. If you disable or do not configure this policy setting, roaming settings are synchronized with the Microsoft Office roaming settings web service and users can access their data from other devices. Existing data in the cloud is not affected by this policy.