How to Modify a Policy
You can modify a policy that is applied to one or more objects to change the properties on all the objects. This procedure outlines how to modify a policy.
Procedure
To modify a policy
In Exchange System Manager, right-click the policy that you want to modify, click Properties, and then use the tabs to modify the policy.
After you have made the necessary modifications, right-click the policy, and then click Apply now to apply the changes.