Allow a Web application server to use on-premise Exchange server to send e-mails

Question

We have a server running Exchange 2010 and one of our service providers want to use it to send their application e-mails, but the application isn't on our network at the moment.

is it possible to allow a web server to use the local mail server to send it's emails?

Answer 1

If you opened up the firewall from the service provider to your Exchange Server for port 25 or used a VPN, yes.

Then create a receive connector for their application:

https://learn.microsoft.com/en-us/exchange/mail-flow/connectors/allow-anonymous-relay?view=exchserver-2019#step-1-create-a-dedicated-receive-connector-for-anonymous-relay