I am posting here for some advice please.
We have just migrated a customer's in-house SBS Exchange 2007 to OneNet but have had to keep one email domain in-house for now (don't ask).
How can I configure their Exchange server to send email to the newly created external OneNet mailboxes from that one in-house email domain? At the moment it appears to just want to route internally (to the old, in-house mailboxes) as it has always done in the past.
I'm thinking something via Exchange Console -> Hub Transport -> Organisation -> Send Connectors - SMTP?