diff --git a/lib/presentation/pages/settings/network_test_page.dart b/lib/presentation/pages/settings/network_test_page.dart
index 905e31f..a8f3141 100644
--- a/lib/presentation/pages/settings/network_test_page.dart
+++ b/lib/presentation/pages/settings/network_test_page.dart
@@ -7,6 +7,7 @@ import 'package:http/http.dart' as http;
 import 'package:url_launcher/url_launcher.dart';
 
 import '../../widgets/desktop_constrained.dart';
+import '../../widgets/toast_helper.dart';
 
 enum _NetworkTestTab { network, service, custom }
 
@@ -20,6 +21,13 @@ class NetworkTestPage extends StatefulWidget {
 class _NetworkTestPageState extends State<NetworkTestPage> {
   static final _panUri = Uri.parse('https://pan.gongyun.org');
   static final _infoUri = Uri.parse('https://www.gongyun.org/appnetinfo.html');
+  static final _primaryIpLookupUri = Uri.parse('https://ipwho.is/');
+  static final _secondaryIpLookupUri = Uri.parse('https://ipapi.co/json/');
+  static const _probeHeaders = {'Cache-Control': 'no-cache'};
+  static const _probeGetFallbackHeaders = {
+    'Cache-Control': 'no-cache',
+    'Range': 'bytes=0-0',
+  };
 
   _NetworkTestTab _tab = _NetworkTestTab.network;
   bool _networkLoading = false;
@@ -44,8 +52,7 @@ class _NetworkTestPageState extends State<NetworkTestPage> {
           IconButton(
             tooltip: '说明',
             icon: const Icon(Icons.info_outline),
-            onPressed: () =>
-                launchUrl(_infoUri, mode: LaunchMode.externalApplication),
+            onPressed: () => _openExternalUrl(_infoUri),
           ),
         ],
       ),
@@ -71,7 +78,7 @@ class _NetworkTestPageState extends State<NetworkTestPage> {
                     ButtonSegment(
                       value: _NetworkTestTab.custom,
                       icon: Icon(Icons.route_outlined),
-                      label: Text('自定义'),
+                      label: Text('自定义线路'),
                     ),
                   ],
                   selected: {_tab},
@@ -129,7 +136,7 @@ class _NetworkTestPageState extends State<NetworkTestPage> {
       context: context,
       builder: (dialogContext) => AlertDialog(
         title: const Text('自定义线路'),
-        content: const Text('此功能暂不可用'),
+        content: const Text('自定义线路为会员功能，当前版本暂未开放。'),
         actions: [
           FilledButton(
             onPressed: () => Navigator.of(dialogContext).pop(),
@@ -140,7 +147,20 @@ class _NetworkTestPageState extends State<NetworkTestPage> {
     );
   }
 
+  Future<void> _openExternalUrl(Uri uri) async {
+    try {
+      final opened = await launchUrl(uri, mode: LaunchMode.externalApplication);
+      if (!opened) {
+        ToastHelper.failure('无法打开链接: $uri');
+      }
+    } catch (e) {
+      ToastHelper.failure('无法打开链接: $e');
+    }
+  }
+
   Future<void> _runNetworkTest() async {
+    if (_networkLoading) return;
+
     setState(() {
       _networkLoading = true;
       _networkError = null;
@@ -171,6 +191,8 @@ class _NetworkTestPageState extends State<NetworkTestPage> {
   }
 
   Future<void> _runServiceTest() async {
+    if (_serviceLoading) return;
+
     setState(() {
       _serviceLoading = true;
       _serviceError = null;
@@ -246,7 +268,7 @@ class _NetworkTestPageState extends State<NetworkTestPage> {
   Future<_IpInfo> _fetchIpInfo() async {
     try {
       final response = await http
-          .get(Uri.parse('https://ipwho.is/'))
+          .get(_primaryIpLookupUri)
           .timeout(const Duration(seconds: 8));
       if (response.statusCode >= 200 && response.statusCode < 300) {
         final data = jsonDecode(response.body) as Map<String, dynamic>;
@@ -270,7 +292,7 @@ class _NetworkTestPageState extends State<NetworkTestPage> {
 
     try {
       final response = await http
-          .get(Uri.parse('https://ipapi.co/json/'))
+          .get(_secondaryIpLookupUri)
           .timeout(const Duration(seconds: 8));
       if (response.statusCode >= 200 && response.statusCode < 300) {
         final data = jsonDecode(response.body) as Map<String, dynamic>;
@@ -307,7 +329,7 @@ class _NetworkTestPageState extends State<NetworkTestPage> {
       final response = await http
           .get(
             Uri.parse('https://status.gongyun.org/api/monitor?pageId=$pageId'),
-            headers: const {'Cache-Control': 'no-cache'},
+            headers: _probeHeaders,
           )
           .timeout(const Duration(seconds: 10));
       if (response.statusCode < 200 || response.statusCode >= 300) {
@@ -367,13 +389,19 @@ class _NetworkTestPageState extends State<NetworkTestPage> {
   }) async {
     final stopwatch = Stopwatch()..start();
     try {
-      final response = await http
-          .get(uri, headers: const {'Cache-Control': 'no-cache'})
+      var response = await http
+          .head(uri, headers: _probeHeaders)
           .timeout(const Duration(seconds: 8));
+      if (_shouldRetryProbeWithGet(response.statusCode)) {
+        response = await http
+            .get(uri, headers: _probeGetFallbackHeaders)
+            .timeout(const Duration(seconds: 8));
+      }
       stopwatch.stop();
-      final isHealthy = healthyStatusCodes.isEmpty
-          ? response.statusCode >= 200 && response.statusCode < 500
-          : healthyStatusCodes.contains(response.statusCode);
+      final isHealthy = _isHealthyStatus(
+        response.statusCode,
+        healthyStatusCodes,
+      );
       return _ProbeResult(
         reachable: isHealthy,
         latencyMs: stopwatch.elapsedMilliseconds,
@@ -384,6 +412,17 @@ class _NetworkTestPageState extends State<NetworkTestPage> {
     }
   }
 
+  bool _shouldRetryProbeWithGet(int statusCode) {
+    return statusCode == 403 || statusCode == 405 || statusCode == 501;
+  }
+
+  bool _isHealthyStatus(int statusCode, Set<int> healthyStatusCodes) {
+    if (healthyStatusCodes.isNotEmpty) {
+      return healthyStatusCodes.contains(statusCode);
+    }
+    return statusCode >= 200 && statusCode < 500;
+  }
+
   Future<_StabilityResult> _testStability(Uri uri) async {
     final latencies = <int>[];
     var successCount = 0;
@@ -438,7 +477,7 @@ class _NetworkPanel extends StatelessWidget {
             if (loading) const LinearProgressIndicator(),
             if (error != null) _ErrorText(error!),
             _InfoRow(
-              label: '公云存储官网访问测试',
+              label: '公云存储网盘访问测试',
               value: data == null ? '检测中' : (data.panReachable ? '正常' : '离线'),
               valueColor: _statusColor(context, data?.panReachable),
             ),
@@ -463,11 +502,14 @@ class _NetworkPanel extends StatelessWidget {
           title: '说明',
           children: const [
             _DescriptionLine('公云存储作为国际化云存储产品，已接入Cloudflare CDN作为全球加速引擎。'),
+            _DescriptionLine(
+              '当前网络 IP 地址、AS 与运营商信息通过第三方服务 ipwho.is 查询；如该服务不可用，将使用 ipapi.co 作为备用查询。',
+            ),
             _DescriptionLine(
               '由于部分国家/地区有法律法规限制与审查，可能会出现包括但不限于网络波动、网络丢包以及网络连接不稳定现象',
             ),
             _DescriptionLine(
-              '如诺出现网络连接问题您可将本页面内容向公云存储团队进行报告，团队会根据相关诊断线索进行排查与优化。',
+              '如若出现网络连接问题，您可将本页面内容向公云存储团队报告，团队会根据相关诊断线索进行排查与优化。',
             ),
           ],
         ),
diff --git a/lib/presentation/pages/settings/settings_page.dart b/lib/presentation/pages/settings/settings_page.dart
index c5323a6..af6a304 100644
--- a/lib/presentation/pages/settings/settings_page.dart
+++ b/lib/presentation/pages/settings/settings_page.dart
@@ -167,9 +167,8 @@ class _SettingsPageState extends State<SettingsPage> {
                   subtitle: const Text('gongyun_app'),
                   trailing: const Icon(Icons.open_in_new, size: 16),
                   onTap: () {
-                    launchUrl(
+                    _openExternalUrl(
                       Uri.parse('https://git.saont.net/gongyun/app'),
-                      mode: LaunchMode.externalApplication,
                     );
                   },
                 ),
@@ -179,11 +178,10 @@ class _SettingsPageState extends State<SettingsPage> {
                   subtitle: const Text('cloudreve4_flutter'),
                   trailing: const Icon(Icons.open_in_new, size: 16),
                   onTap: () {
-                    launchUrl(
+                    _openExternalUrl(
                       Uri.parse(
                         'https://github.com/LimoYuan/cloudreve4_flutter',
                       ),
-                      mode: LaunchMode.externalApplication,
                     );
                   },
                 ),
@@ -405,13 +403,16 @@ class _SettingsPageState extends State<SettingsPage> {
     return AnimatedBuilder(
       animation: UpdateService.instance,
       builder: (context, _) {
+        final hasUpdate = UpdateService.instance.hasUpdate;
         return ListTile(
-          leading: const Icon(Icons.tag),
+          leading: Icon(
+            hasUpdate ? Icons.new_releases_outlined : Icons.tag,
+            color: hasUpdate ? Theme.of(context).colorScheme.primary : null,
+          ),
           title: const Text('版本号'),
           subtitle: Text(_appVersion.isEmpty ? '加载中...' : _appVersion),
-          trailing: UpdateService.instance.hasUpdate
-              ? const _BlinkingUpdateDot()
-              : null,
+          onTap: hasUpdate ? () => _openDownloadsPage() : null,
+          trailing: hasUpdate ? const _UpdateAvailableBadge() : null,
         );
       },
     );
@@ -562,6 +563,25 @@ class _SettingsPageState extends State<SettingsPage> {
     }
   }
 
+  Future<void> _openExternalUrl(Uri uri) async {
+    try {
+      final opened = await launchUrl(uri, mode: LaunchMode.externalApplication);
+      if (!opened) {
+        ToastHelper.failure('无法打开链接: $uri');
+      }
+    } catch (e) {
+      ToastHelper.failure('无法打开链接: $e');
+    }
+  }
+
+  Future<void> _openDownloadsPage() async {
+    try {
+      await UpdateService.instance.openDownloadsPage();
+    } catch (e) {
+      ToastHelper.failure('打开下载页面失败: $e');
+    }
+  }
+
   Future<void> _openNetworkTest(BuildContext context) async {
     final agreed = await showDialog<bool>(
       context: context,
@@ -569,13 +589,11 @@ class _SettingsPageState extends State<SettingsPage> {
       builder: (dialogContext) => AlertDialog(
         title: const Text('会话信息授权'),
         content: _NetworkTestConsentText(
-          onOpenPrivacy: () => launchUrl(
+          onOpenPrivacy: () => _openExternalUrl(
             Uri.parse('https://www.gongyun.org/policy/privacy.html'),
-            mode: LaunchMode.externalApplication,
           ),
-          onOpenTerms: () => launchUrl(
+          onOpenTerms: () => _openExternalUrl(
             Uri.parse('https://www.gongyun.org/policy/terms.html'),
-            mode: LaunchMode.externalApplication,
           ),
         ),
         actions: [
@@ -641,14 +659,14 @@ class _SettingsPageState extends State<SettingsPage> {
   }
 }
 
-class _BlinkingUpdateDot extends StatefulWidget {
-  const _BlinkingUpdateDot();
+class _UpdateAvailableBadge extends StatefulWidget {
+  const _UpdateAvailableBadge();
 
   @override
-  State<_BlinkingUpdateDot> createState() => _BlinkingUpdateDotState();
+  State<_UpdateAvailableBadge> createState() => _UpdateAvailableBadgeState();
 }
 
-class _BlinkingUpdateDotState extends State<_BlinkingUpdateDot>
+class _UpdateAvailableBadgeState extends State<_UpdateAvailableBadge>
     with SingleTickerProviderStateMixin {
   late final AnimationController _controller;
   late final Animation<double> _opacity;
@@ -674,15 +692,31 @@ class _BlinkingUpdateDotState extends State<_BlinkingUpdateDot>
 
   @override
   Widget build(BuildContext context) {
+    final colorScheme = Theme.of(context).colorScheme;
     return FadeTransition(
       opacity: _opacity,
-      child: Container(
-        width: 10,
-        height: 10,
-        decoration: const BoxDecoration(
-          color: Colors.red,
-          shape: BoxShape.circle,
-        ),
+      child: Row(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          Container(
+            width: 8,
+            height: 8,
+            decoration: BoxDecoration(
+              color: colorScheme.error,
+              shape: BoxShape.circle,
+            ),
+          ),
+          const SizedBox(width: 6),
+          Text(
+            '发现新版本',
+            style: TextStyle(
+              color: colorScheme.error,
+              fontWeight: FontWeight.w700,
+            ),
+          ),
+          const SizedBox(width: 4),
+          Icon(Icons.chevron_right, size: 18, color: colorScheme.error),
+        ],
       ),
     );
   }
@@ -734,9 +768,8 @@ class _NetworkTestConsentTextState extends State<_NetworkTestConsentText> {
       fontWeight: FontWeight.w700,
     );
 
-    return RichText(
-      text: TextSpan(
-        style: Theme.of(context).textTheme.bodyMedium,
+    return Text.rich(
+      TextSpan(
         children: [
           const TextSpan(text: '您需同意'),
           TextSpan(
@@ -750,7 +783,10 @@ class _NetworkTestConsentTextState extends State<_NetworkTestConsentText> {
             style: linkStyle,
             recognizer: _termsRecognizer,
           ),
-          const TextSpan(text: '方可进入网络测试页。'),
+          const TextSpan(
+            text:
+                '方可进入网络测试页。测试会访问公云存储服务，并通过第三方服务 ipwho.is 查询当前网络 IP、AS 与运营商信息；如 ipwho.is 不可用，将使用 ipapi.co 作为备用查询。',
+          ),
         ],
       ),
     );
diff --git a/lib/services/update_service.dart b/lib/services/update_service.dart
index 4f3bbde..ce012b7 100644
--- a/lib/services/update_service.dart
+++ b/lib/services/update_service.dart
@@ -15,7 +15,16 @@ import '../data/models/app_update_model.dart';
 import 'storage_service.dart';
 
 class UpdateService extends ChangeNotifier {
-  UpdateService._();
+  UpdateService._()
+    : _dio = Dio(_dioOptions),
+      _packageInfoProvider = PackageInfo.fromPlatform;
+
+  @visibleForTesting
+  UpdateService.test({
+    Dio? dio,
+    Future<PackageInfo> Function()? packageInfoProvider,
+  }) : _dio = dio ?? Dio(_dioOptions),
+       _packageInfoProvider = packageInfoProvider ?? PackageInfo.fromPlatform;
 
   static final UpdateService instance = UpdateService._();
 
@@ -29,15 +38,16 @@ class UpdateService extends ChangeNotifier {
     'https://www.gongyun.org/downloads.html',
   );
 
-  final Dio _dio = Dio(
-    BaseOptions(
-      connectTimeout: const Duration(seconds: 12),
-      receiveTimeout: const Duration(seconds: 20),
-      followRedirects: true,
-      responseType: ResponseType.plain,
-    ),
+  static final BaseOptions _dioOptions = BaseOptions(
+    connectTimeout: const Duration(seconds: 12),
+    receiveTimeout: const Duration(seconds: 20),
+    followRedirects: true,
+    responseType: ResponseType.plain,
   );
 
+  final Dio _dio;
+  final Future<PackageInfo> Function() _packageInfoProvider;
+
   bool _checking = false;
   AppUpdateInfo? _availableUpdate;
 
@@ -49,7 +59,7 @@ class UpdateService extends ChangeNotifier {
 
     _checking = true;
     try {
-      final current = await PackageInfo.fromPlatform();
+      final current = await _packageInfoProvider();
       final latest = await _fetchLatestRelease(currentVersion: current.version);
       if (latest == null ||
           _compareVersions(latest.version, current.version) <= 0) {
diff --git a/test/services/update_service_test.dart b/test/services/update_service_test.dart
new file mode 100644
index 0000000..b0631f5
--- /dev/null
+++ b/test/services/update_service_test.dart
@@ -0,0 +1,23 @@
+import 'package:cloudreve4_flutter/services/update_service.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  group('UpdateService', () {
+    test(
+      'checkForUpdate releases checking flag when package info fails',
+      () async {
+        var calls = 0;
+        final service = UpdateService.test(
+          packageInfoProvider: () async {
+            calls += 1;
+            throw Exception('package info unavailable');
+          },
+        );
+
+        expect(await service.checkForUpdate(), isNull);
+        expect(await service.checkForUpdate(), isNull);
+        expect(calls, 2);
+      },
+    );
+  });
+}