Open Settings
and select General > Security > Protected content > Track protected object.
Other devices can send you media files that are protected by usage rights and for which you need activation keys. Some activation keys contain unique IDs that allow the media file provider to track the sending device. Some providers use this service to reward people who distribute their media files to others who buy usage rights for the files.
To allow media file providers to track the files sent to you, select Yes.
To save your setting, select Back.