But!!! I am going crazy... some internal users are still able to email to the 365group even though they have been added to the Reject Messages from list in the Group many days ago..I have tried to run Get-MailboxJunkEmailConfiguration -Identity my365publicgroup@mydomain.com This command fails on 365 groups? How can I trouble shoot 365Groups. Or better yet assigning blocked senders via powershell? I have to stop mail from arriving to the group from users that are blocked in the group delivery management.. Its not working...Help:)
Are those users members of the Group or just external users? In the later case, you can simply block external users send e-mails in the Group configuration (using the UI)...if you need more granular configuration, use the Set-UnifiedGroup cmdlet
If you want to restrict who can send to a group, use the Set-UnifiedGroup and the -AcceptMessagesOnlyFrom* parameters. Not the MailboxJunkEmailConfiguration ones.
