Important Announcement from Microsoft on 7/31/19 to all Office 365 customers. Beginning 8/15/19, Microsoft will enable a new setting that allows all Office 365 users to send data to their personal cloud storage accounts (Google Drive, Facebook, Consumer OneDrive, etc). This will take effect even if you had disabled a similar setting in the past. Here is the new command to turn this off.

Here is the email all Office 365 administrators should have received relating to this roadmap ID 52597

‪The old way of hardening will no longer work using these cmds: set-owamailboxpolicy -DropboxAttachmentsEnabled $false -BoxAttachmentsEnabled -GoogleDriveAttachmentsEnabled $false -ThirdPartyAttachmentsEnabled $false‬

This is not the first time Microsoft has changed the default settings or experience which has a security / governance impact.