The Community provides the ability to receive email notifications of new discussions, Knowledge Base categories, individual posts, and individual Knowledge Base articles. To receive notifications you must subscribe to each discussion group or Knowledge Base category of interest.
How to Subscribe/Unsubscribe?
Navigate to the group/category of interest and select Subscribe under Board Options
You can Unsubscribe by performing the same steps or under My Subscriptions
Click on your Community Name to display the Preferance Menu