Routing—If no workflow action is taken on a message processed by the Incoming Message Rules, then the message is routed to the General Pool. If you want the messages to go to a queue other than the General Pool, make the last rule in the list a routing rule that sends all messages there. This rule would have only an action and no attributes. It would, therefore, apply to all messages.
Active check box—Use the Active check box in the Rules window for rules that process messages related to a specific transient event, such as a holiday or temporary web site problem. The Active check box makes it easy to turn these rules on when needed.
Stop processing—Be careful not to write rules that allow both an autoresponse and an acknowledgment to be sent for the same message. To avoid this problem, you can use the Stop processing flag after all rules that send an autoresponse, and make sure all rules that send acknowledgments are at the end of the rule set. This ensures that any message that triggers an autoresponse does not also trigger an acknowledgment.
Another way to avoid this problem is to add a label called Acknowledged whenever an acknowledge action is performed and a label called Autoresponse whenever an autoresponse is being sent. Then create a rule that prevents later autoresponses or acknowledgments from being sent.
Filter rules—Be sure to test your Filter rules to make sure that valid messages are not being deleted as irrelevant. Rather than deleting irrelevant messages, you might want to route them to a special queue that can be monitored by an administrator.
Learn about rules and rule groups.