How to block email app

Copper Contributor

Hi. We have a strange problem. We are a school and our emails are hosted by IINET. We recently subscribed to Microsoft 365, mainly for Word, PP & XL, but our exchange was always to be hosted by IINET.  We used our standard staff email addresses as the logon to the M365 user workbench.


Everything is working fine, but sometimes a staff member will inadvertantly use M365 Outlook (instead of the normal IINET OWA)  to send an email to another staff member which never seems to leave the Microsoft cloud. e.g. Staff_A sends an email to Staff_B using M365 Outlook. I guess that M365 sees that Staff_Member_B has a M365 account, so it never delivers the email externally to IINET.  Staff_B can see that email in his M365 Outlook app, but not in IINET.


I'm sure the Admin centre has a way to deal with this situation, but I can't see it. Can anyone please point me in the right direction?  Thx.

0 Replies