EEEU, which stands for Everyone Except External Users, is a permission setting used in SharePoint Online and OneDrive to manage access to content.
This setting allows all internal users in an organization to access certain content while excluding external users.
While the use of this sharing option was discouraged by Microsoft (Grant Everyone claim to external users in Microsoft 365 – Microsoft 365 | Microsoft Learn) due to high risk of over sharing content, it has been overseen by SharePoint administrators.
Well, starting April 10, 2025 and up to September 30, 2025, Microsoft is planning to run a detection logic on M365 tenant to remove the EEEU permission from the root site and each user’s OneDrive.
Only the EEEU permission will be removed, all others will stay as is.
It is a good idea to review your SharePoint Online access control to identify if you are still using EEEU and identify the best replacement option using Entra ID dynamic group (recommended).