Forum Discussion
Sending emails after after your email was hacked
My email was hacked and know when I send out an email this delivery "Your message couldn't be delivered because you weren't recognized as a valid sender. The most common reason for this is that y...
Hi, send this to your administrator https://docs.microsoft.com/en-us/microsoft-365/security/office-365-security/removing-user-from-restricted-users-portal-after-spam?view=o365-worldwide