External Users Access Change in Office 365

If you receive the Office 365 Message Center Update Notifications you know that it’s rare to see a “Major Update Notification” that you must act upon quickly, but that is exactly what we received on Saturday February 24th. Starting on March 23, 2018 external users will no longer belong to the following groups in SharePoint Online:…
— Lees op blogs.ibs.com/2018/02/26/external-users-access-change-in-office-365/