I'm working on enabling a content filter in my iOS app using NEFilterManager and NEFilterProviderConfiguration. The setup works perfectly in debug builds when running via Xcode, but fails on TestFlight builds with the following error: **Failed to save filter settings: permission denied ** **Here is my current implementation: ** (void)startContentFilter { NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults]; [userDefaults synchronize]; [[NEFilterManager sharedManager] loadFromPreferencesWithCompletionHandler:^(NSError * _Nullable error) { dispatch_async(dispatch_get_main_queue(), ^{ if (error) { NSLog(@"Failed to load filter: %@", error.localizedDescription); [self showAlertWithTitle:@"Error" message:[NSString stringWithFormat:@"Failed to load content filter: %@", error.localizedDescription]]; return; } NEFilterProviderConfiguration *filterConfig = [[NEFilterProviderConfiguration alloc] init]; filterConfig.filterSockets = YES; filterConfig.filterBrowsers = YES; NEFilterManager *manager = [NEFilterManager sharedManager]; manager.providerConfiguration = filterConfig; manager.enabled = YES; [manager saveToPreferencesWithCompletionHandler:^(NSError * _Nullable error) { dispatch_async(dispatch_get_main_queue(), ^{ if (error) { NSLog(@"Failed to save filter settings: %@", error.localizedDescription); [self showAlertWithTitle:@"Error" message:[NSString stringWithFormat:@"Failed to save filter settings: %@", error.localizedDescription]]; } else { NSLog(@"Content filter enabled successfully!"); [self showAlertWithTitle:@"Success" message:@"Content filter enabled successfully!"]; } }); }]; }); }]; } **What I've tried: ** Ensured the com.apple.developer.networking.networkextension entitlement is set in both the app and system extension. The Network extension target includes content-filter-provider. Tested only on physical devices. App works in development build, but not from TestFlight. **My questions: ** Why does saveToPreferencesWithCompletionHandler fail with “permission denied” on TestFlight? Are there special entitlements required for using NEFilterManager in production/TestFlight builds? Is MDM (Mobile Device Management) required to deploy apps using content filters? Has anyone successfully implemented NEFilterProviderConfiguration in production, and if so, how?