What causes "创建服务 {serv_name} 时，返回值为空！" in OdysseusYuan/LKY_OfficeTools?

Run as administrator (Create requires privileges anyway for sc create).

OdysseusYuan/LKY_OfficeTools · error · Exception

创建服务 {serv_name} 时，返回值为空！

Error message

创建服务 {serv_name} 时，返回值为空！

What it means

Thrown in Com_ServiceOS.Config.Create when the stdout captured from `sc create ...` via Com_ExeOS.Run.Cmd is null or empty (Com_ServiceOS.cs:303-305). Run.Cmd only returns null inside its own catch (cmd.exe launch or stdio-redirect failure), so an empty result indicates the command never produced output rather than an sc-level failure (access-denied still yields non-empty text). Create catches the throw, logs it, and returns false (Com_ServiceOS.cs:326-330).

Source

Thrown at LKY_OfficeTools/Common/Com_ServiceOS.cs:305

            internal static bool Create(string serv_name, string serv_runpath, string serv_displayname, string serv_description = null)
            {
                try
                {
                    if (Query.IsCreated(serv_name))
                    {
                        //已经创建服务，直接返回真
                        return true;
                    }
                    else
                    {
                        //未安装，开始安装
                        string cmd_install = $"sc create \"{serv_name}\" binPath=\"{serv_runpath}\" start=auto DisplayName=\"{serv_displayname}\"";
                        var install_result = Com_ExeOS.Run.Cmd(cmd_install);

                        //非空判断，若返回值为空，则为假
                        if (string.IsNullOrEmpty(install_result))
                        {
                            throw new Exception($"创建服务 {serv_name} 时，返回值为空！");
                        }

                        //判断是否安装成功
                        if (install_result.Contains("成功") || install_result.ToLower().Contains("success"))
                        {
                            //描述信息不为空，配置描述信息
                            if (!string.IsNullOrEmpty(serv_description))
                            {
                                Modify.Description(serv_name, serv_description);
                            }

                            //无论修改描述信息是否成功，均返回成功
                            return true;
                        }
                        else
                        {
                            return false;
                        }

View on GitHub (pinned to 6f9a1bd471)

Solutions

Run as administrator (Create requires privileges anyway for sc create).
Verify cmd.exe is reachable on PATH and not blocked by policy.
Reproduce by running the exact `sc create ...` string from a real console.
Inspect the application log (Lib_AppLog) for the underlying exception written by Run.Cmd's catch.

Example fix

// before
bool ok = Com_ServiceOS.Config.Create(name, path, display);

// after
if (string.IsNullOrEmpty(Com_ExeOS.Run.Cmd("ver"))) { /* cmd unavailable; fix environment */ return false; }
bool ok = Com_ServiceOS.Config.Create(name, path, display);

Defensive patterns

Strategy: validation

Validate before calling

if (string.IsNullOrEmpty(Com_ExeOS.Run.Cmd("ver"))) { /* cmd unavailable; fix env */ return false; }
bool ok = Com_ServiceOS.Config.Create(name, path, display, desc);

Prevention

Create swallows the throw and returns false; check the bool return and the log.
Run elevated; sc create requires administrator privileges.
Ensure cmd.exe is reachable on PATH and not blocked by policy.
Reproduce the exact `sc create ...` string in a console when debugging.

When it happens

Trigger: Run.Cmd throws because cmd.exe cannot be started, standard-output redirection fails, or the process is killed before emitting output. Extremely unlikely from a plain sc access-denied, which still prints an error string.

Common situations: cmd.exe missing/off-path on a stripped image; an aggressive security product blocking child cmd.exe; stdio handle exhaustion; antivirus interfering with redirected console IO.

Related errors

AI-assisted analysis of OdysseusYuan/LKY_OfficeTools@6f9a1bd471 (2026-08-13). Data as JSON: /api/errors/22c2e8de590d3871. Report an issue: GitHub.