The notification can be inactivated through two areas:
  1. Navigate to onMessage.
  2. Select Communication > Notification > Notifications.
  3. Select Category: Event Registration.
  4. Click View.
  5. To the right of the "Event Registration Processed" notification under your form, click Edit.
  6. Un-check the "Active" box.
  7. Save.
  8. Do this for any form you want to turn off Registration Processed notifications for.
Alternatively:
  1. Navigate to onMessage.
  2. Select Approval > Event Registration.
  3. Click Edit to the right of your Registration form.
  4. On the left under Edit Registration, click the Notifications link.
  5. Click Edit to the right of Event Registration Processed.
  6. Un-check the "Active" box.
  7. Save.