Symptoms

When using a Send an Email Rule, the following error is given: No connection could be made because the target machine actively refused it.

The IP that its reporting is the Exchange Server, however, this should not be used for SMTP. There is another server.
 

Diagnoses

The Mail Server contained the incorrect "Field Value" for the desired configuration.
 

Resolution

To change the Mail Server configuration following the steps below:

1. Using K2 Workspace access Development or Production >> Environment Fields >> Mail Server within Environment Library
2. Select Mail Server and Edit
3. Change the 'Field Value' from your exchange server to your desired SMTP server.
4. Restart K2 services and run test.