Hi,
We have an EOP subscription pointing to our on premise Exchange 2010 server. When EOP sends a custom message to a recipient the sending address is postmaster@ourdomain.com. We want to change this to itsupport@ourdomain.com.
I can find a PowerShell commandlet that will allow you to change the default postmaster address for Exchange online, Set-TransportConfig -ExternalPostmasterAddress <email address> but this command is not recognized in EOP.
Can this be done without an Exchange Online tenant?
Cheers,
Jason