Property TWPRTFStyleCollection.LockMode : TWPRTFStyleCollectionLockModeUnit: WPRTEDefsClass: WPRTEDefs.TWPRTFStyleCollectionDescription Using the property LockMode it is possible to protect the style collection. Any load or clear method will be aborted if required. This is esspecially usefull if you need to avoid adding styles through Clipboard operations.