Try to reset setting and retry when failed

shadowsocks-csharp/Controller/System/SystemProxy.cs

@@ -7,16 +7,13 @@ namespace Shadowsocks.Controller
 {
     public static class SystemProxy
     {
-        private static bool failed = false;
-
         private static string GetTimestamp(DateTime value)
         {
             return value.ToString("yyyyMMddHHmmssfff");
         }
 
-        public static void Update(Configuration config, bool forceDisable, PACServer pacSrv)
+        public static void Update(Configuration config, bool forceDisable, PACServer pacSrv, bool noRetry = false)
         {
-            if (failed) return;
             bool global = config.global;
             bool enabled = config.enabled;
 
@@ -55,18 +52,18 @@ namespace Shadowsocks.Controller
             catch (ProxyException ex)
             {
                 Logging.LogUsefulException(ex);
-                switch (ex.Type)
+                if (ex.Type != ProxyExceptionType.Unspecific && !noRetry)
+                {
+                    var ret = MessageBox.Show(I18N.GetString("Error occured when process proxy setting, do you want reset current setting and retry?"), I18N.GetString("Shadowsocks"), MessageBoxButtons.YesNo, MessageBoxIcon.Warning);
+                    if (ret == DialogResult.Yes)
+                    {
+                        Sysproxy.ResetIEProxy();
+                        Update(config, forceDisable, pacSrv, true);
+                    }
+                }
+                else
                 {
-                    case ProxyExceptionType.FailToRun:
-                        MessageBox.Show(I18N.GetString("Error when running sysproxy, check your proxy config"), I18N.GetString("Shadowsocks"));
-                        break;
-                    case ProxyExceptionType.QueryReturnMalformed:
-                    case ProxyExceptionType.QueryReturnEmpty:
-                        MessageBox.Show(I18N.GetString("Can't query proxy config, check your proxy config"), I18N.GetString("Shadowsocks"));
-                        break;
-                    case ProxyExceptionType.SysproxyExitError:
-                        MessageBox.Show(I18N.GetString("Sysproxy return a error:") + ex.Message, I18N.GetString("Shadowsocks"));
-                        break;
+                    MessageBox.Show(I18N.GetString("Unrecoverable proxy setting error occured, see log for detail"), I18N.GetString("Shadowsocks"), MessageBoxButtons.OK, MessageBoxIcon.Error);
                 }
             }
         }

shadowsocks-csharp/Data/ja.txt

@@ -149,6 +149,5 @@ Register hotkey failed=ホットキーの登錄に失敗しました。
 Cannot parse hotkey: {0}=ホットキーを解析できません: {0}
 Timeout is invalid, it should not exceed {0}=タイムアウト値が無効です。{0} 以下の値を指定して下さい。
 
-Error when running sysproxy, check your proxy config=执行sysproxy时发生错误，请检查你的系统代理设置
-Can't query proxy config, check your proxy config=无法解析代理配置，请检查你的系统代理设置
-Sysproxy return a error:=sysproxy报告了一个错误：
+Error occured when process proxy setting, do you want reset current setting and retry?=处理代理设置时发生错误，是否重置当前代理设置并重试？
+Unrecoverable proxy setting error occured, see log for detail=发生不可恢复的代理设置错误，查看日志以取得详情

shadowsocks-csharp/Data/zh_CN.txt

@@ -149,6 +149,5 @@ Register hotkey failed=注册快捷键失败
 Cannot parse hotkey: {0}=解析快捷键失败: {0}
 Timeout is invalid, it should not exceed {0}=超时无效，不应超过 {0}
 
-Error when running sysproxy, check your proxy config=执行sysproxy时发生错误，请检查你的系统代理设置
-Can't query proxy config, check your proxy config=无法解析代理配置，请检查你的系统代理设置
-Sysproxy return a error:=sysproxy报告了一个错误：
+Error occured when process proxy setting, do you want reset current setting and retry?=处理代理设置时发生错误，是否重置当前代理设置并重试？
+Unrecoverable proxy setting error occured, see log for detail=发生不可恢复的代理设置错误，查看日志以取得详情

shadowsocks-csharp/Data/zh_TW.txt

@@ -149,6 +149,5 @@ Register hotkey failed=註冊快速鍵失敗
 Cannot parse hotkey: {0}=剖析快速鍵失敗: {0}
 Timeout is invalid, it should not exceed {0}=逾時無效，不應超過 {0}
 
-Error when running sysproxy, check your proxy config=执行sysproxy时发生错误，请检查你的系统代理设置
-Can't query proxy config, check your proxy config=无法解析代理配置，请检查你的系统代理设置
-Sysproxy return a error:=sysproxy报告了一个错误：
+Error occured when process proxy setting, do you want reset current setting and retry?=处理代理设置时发生错误，是否重置当前代理设置并重试？
+Unrecoverable proxy setting error occured, see log for detail=发生不可恢复的代理设置错误，查看日志以取得详情

shadowsocks-csharp/Util/SystemProxy/Sysproxy.cs

@@ -82,6 +82,26 @@ namespace Shadowsocks.Util.SystemProxy
             ExecSysproxy(arguments);
         }
 
+
+        // set system proxy to 1 (null) (null) (null)
+        public static bool ResetIEProxy()
+        {
+            try
+            {
+            // clear user-wininet.json
+            _userSettings = new SysproxyConfig();
+            Save();
+            // clear system setting
+            ExecSysproxy("set 1 - - -");
+            }
+            catch (Exception e)
+            {
+                return false;
+            }
+
+            return true;
+        }
+
         private static void ExecSysproxy(string arguments)
         {
             // using event to avoid hanging when redirect standard output/error
@@ -146,8 +166,6 @@ namespace Shadowsocks.Util.SystemProxy
                         // log the arguements
                         throw new ProxyException(ProxyExceptionType.FailToRun, process.StartInfo.Arguments, e);
                     }
-
-
                     var stderr = error.ToString();
                     var stdout = output.ToString();