When logged into Postmark select the server, and go to the “Settings” tab. There you can enable open tracking for that server.
Once enabled, all outbound HTML emails being sent through this Server will track all opens.
You can modify the TrackOpens field for a specific Server using the Server API to edit an existing server.
You can modify the TrackOpens field using the Servers API to edit existing servers. You can also use the Servers API to create servers and set the TrackOpens field at the same time.
