Before you can send email from an Application Builder application, you must:
Log in to Oracle Application Express Administration Services and configure the email settings on the Instance Settings page. See in Oracle Application Express Administration Guide.
If you are running Oracle Application Express with Oracle Database 11g release 1 (11.1), you must enable outbound mail. In Oracle Database 11g release 1 (11.1), the ability to interact with network services is disabled by default. See "Enabling Network Services in Oracle Database 11g" in Oracle Application Express Application Builder User's Guide.
You can configure Oracle Application Express to automatically email users their login credentials when a new workspace request has been approved. To learn more, see "Specifying a Provisioning Mode"in Oracle Application Express Administration Guide.