Modifying or Removing a Policy
You can modify a policy that is applied to one or more objects to change the properties on all the objects. For detailed instructions, see How to Modify a Policy.
To change the properties on all the objects individually, you can also remove an object from the control of a policy or delete the policy itself.
For detailed instructions on removing an object from the control of a policy, see How to Remove an Object from the Control of a Policy.
For detailed instructions on deleting a policy, see How to Delete a Policy.
After a policy has been applied, settings associated with that policy remain intact on associated objects, even after an object has been removed from policy control or a policy itself has been deleted. If you want to change the settings that a policy applies, you must change them on the individual server, mailbox store, or public folder store.