Allow only specific domain to email a distribution group
I’d like to allow only a specific external sender domain to send email to our distribution group (DG) in M365. (The DG is actually a mail-enabled security group synced from AD.) I see that a mail-flow rule doesn’t process until after the DG is expanded, so can’t match the DG as the recipient. I see that the DG has an attribute dLMemSubmitPerms to specify who’s permitted to send to the group, but I think that is only for objects in AD and wouldn’t be able to use an external domain? When I try to modify dLMemSubmitPerms I get an error anyway.
So how can this be done?
I’d like to allow only a specific external sender domain to send email to our distribution group (DG) in M365. (The DG is actually a mail-enabled security group synced from AD.) I see that a mail-flow rule doesn’t process until after the DG is expanded, so can’t match the DG as the recipient. I see that the DG has an attribute dLMemSubmitPerms to specify who’s permitted to send to the group, but I think that is only for objects in AD and wouldn’t be able to use an external domain? When I try to modify dLMemSubmitPerms I get an error anyway.So how can this be done? Read More