Enabling External Outlook Web Access to On-Premises Exchange Server
I'm trying to enable external Outlook Web Access (OWA) to an on-premises Exchange Server 2013.
OWA works fine on the internal network and mail.[mycompany.com]/owa is correctly enabled on the server.
However, I just can't get external access to work.
The server is connected to the internet via BT Business Hub with the firewall disabled and
port 443 forwarded to the external interface of Watchguard Firebox T15.
I've set up an SNAT from all external on port 443 to the internal IP address of the Exchange Server. I've then created a new HTTPS policy with a proxy to allow the appropriate traffic but I just can't get it to work.
The firewall policies arehttps://drive.google.com/file/d/1yqZexDDKdwxmzp9nrXx_8wlhvixXLP4h/view?usp=sharing
The policy details are https://drive.google.com/file/d/1o__9PP9BgD4Xh3YcRbyJkxgtZtnx3afj/view?usp=sharing
and the proxy details are https://drive.google.com/file/d/1BhEl4xqO9XgZec9SSKkexa-atjvXan6x/view?usp=sharing