You can delete any custom entity type you created as long as it is not assigned to a policy. If an entity type is assigned to a policy, you must remove it from the policy before you can delete it. Preinstalled entity types (identified by the lock icon) cannot be deleted.
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Expand the Manage section in the left navigation menu.
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Click Entity types.
Locate the entity type you want to delete.
Click the ellipses (…) at the end of the row.
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Select Delete. (Note that this option is unavailable for preinstalled entity types.)
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Click Delete in the menu that displays.
Select OK when prompted to verify you want to delete the entity type.
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If an entity type is assigned to a policy, you will receive a message indicating the policy that contains the entity type. Use the Go to Polices button to view a list of the polices that contain the entity type. You will need to remove the entity type from all the polices before you can delete it.
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