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Select Content.
Select Entity types.
Locate the entity type you want to delete.
Click the ellipses (…) at the end of the row.
Select Delete. (Note that this option is unavailable for preinstalled entity types.)
Select Yes when prompted to verify you want to delete the entity type.
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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