External Sharing in OneDrive

OneDrive for Business is a personal repository that people can use to store and sync files across multiple devices. In this sense, OneDrive functions like a home directory or personal mapped drive that lets users save files in cloud storage and retrieve them from any device.

Many customers also use OneDrive to share items with other users, although OneDrive wasn’t actually designed for this purpose. As an administrator, you can decide the level of access that external users have to OneDrive files in your organization.

Tenant-wide sharing settings apply to all the OneDrive instances for users in your Microsoft 365 account. There are two portals through which you can configure these sharing settings for OneDrive:
The Sharing page in the SharePoint admin center (Microsoft recommends using this page to configure your OneDrive sharing settings)
The Sharing page in the OneDrive admin center

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