A net send notification will send an alert using the windows messaging service. Please note that on the machine running Overseer, the "Alerter" service needs to be running. On the machine you're sending the notification to, the "Messenger" service needs to be running. If both or one of these is turned off, messages will not be received by the target machine.
To define a new net send notification resource, select File / New Notification / Net Send to open the Notification resource.
Define the name you want your notification to display as, define the computer name or IP you wish to send the notification to, and check whether or not you want this notification to be enabled by default when you define a new resource.
On the bottom of the Email window, you can also click on the "Test" button to test sending an email to the defined address. This will allow you to confirm that the address defined is entered correctly.
On the right hand side, you can also click on "Custom Text" to customize the message sent when an alert goes out. You can define the subject and body of both "Notification on Failure" and "Notification on Recovery" messages.
When you are done defining your "Net Send" resource, click on "OK" to save.