Hello, I'm trying to play a stream video after I downloaded it using a AVAssetDownloadURLSession and aggregateAssetDownloadTask. When I initialise the AVPlayerItem with the AVURLAsset saved locally in the bookmarks it get the -12865 error. What does this code stands for? If I play the video directly from the stream it works fine. This is the code that saves the asset:     func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) {         let userDefaults = UserDefaults.standard         /*          This is the ideal place to begin downloading additional media selections          once the asset itself has finished downloading.          */         guard let task = task as? AVAggregateAssetDownloadTask,             let asset = activeDownloadsMap.removeValue(forKey: task) else { return }         guard let downloadURL = willDownloadToUrlMap.removeValue(forKey: task) else { return }         // Prepare the basic userInfo dictionary that will be posted as part of our notification.         var userInfo = [String: Any]()         userInfo[Asset.Keys.name] = asset.name         if let error = error as NSError? {             switch (error.domain, error.code) {             case (NSURLErrorDomain, NSURLErrorCancelled):                 /*                  This task was canceled, you should perform cleanup using the                  URL saved from AVAssetDownloadDelegate.urlSession(_:assetDownloadTask:didFinishDownloadingTo:).                  */                 guard let localFileLocation = localAsset(withName: asset.name)?.urlAsset.url else { return }                 do {                     try FileManager.default.removeItem(at: localFileLocation)                     userDefaults.removeObject(forKey: asset.name)                 } catch {                     print("An error occured trying to delete the contents on disk for \(asset.name): \(error)")                 }                 userInfo[Asset.Keys.downloadState] = Asset.DownloadState.notDownloaded.rawValue             case (NSURLErrorDomain, NSURLErrorUnknown):                 fatalError("Downloading HLS streams is not supported in the simulator.")             default:                 fatalError("An unexpected error occured \(error.domain)")             }         } else {             do {                 let bookmark = try downloadURL.bookmarkData()                 userDefaults.set(bookmark, forKey: asset.name)             } catch {                 print("Failed to create bookmarkData for download URL.")             }             userInfo[Asset.Keys.downloadState] = Asset.DownloadState.downloaded.rawValue             userInfo[Asset.Keys.downloadSelectionDisplayName] = ""         }         NotificationCenter.default.post(name: .AssetDownloadStateChanged, object: nil, userInfo: userInfo)     }     /// Method called when the an aggregate download task determines the location this asset will be downloaded to.     func urlSession(_ session: URLSession, aggregateAssetDownloadTask: AVAggregateAssetDownloadTask,                     willDownloadTo location: URL) {         /*          This delegate callback should only be used to save the location URL          somewhere in your application. Any additional work should be done in          `URLSessionTaskDelegate.urlSession(_:task:didCompleteWithError:)`.          */         willDownloadToUrlMap[aggregateAssetDownloadTask] = location     } and this one get's the asset back         guard let localFileLocation = userDefaults.value(forKey: name) as? Data else { return nil }                  var bookmarkDataIsStale = false         do {             let url = try URL(resolvingBookmarkData: localFileLocation,                                     bookmarkDataIsStale: &bookmarkDataIsStale)             if bookmarkDataIsStale {                 fatalError("Bookmark data is stale!")             }                          return AVURLAsset(url: url)         } catch {             fatalError("Failed to create URL from bookmark with error: \(error)")         } Thank you