Removing Unused Resources
Use the Resources - Remove Unused tool to delete unused instances of any resource type. You can choose whether or not to be prompted before each delete.
Only resources that are not currently being used by an object can be removed. You can use the Resource Finder to determine which object(s) are using stray resources.
Caution: This utility does NOT detect if a resource is being used dynamically (via script or extended objects). You should ensure that resources are not needed before using this utility.