Powershell 脚本已执行，但从 IIS ASP.NET 站点调用时挂起

Question

这是我的代码：

在 Default.aspx.cs

//Default.aspx.cs is used to create a docx file on server 
//and push to the browser for downloading  
protected void btnSubmit_Click(object sender, EventArgs e)
{
  try
  {
    string strOutFile = string.Empty;
    switch (ExportType.SelectedItem.Value)
    {
      case "TestReport":
        //_strBaseDirectory was defined in web.config and refer to the site wwwroot folder
        strOutFile = _strBaseDirectory + @"Download\" + DateTime.Now.ToString("yyyyMMddHHmmssfff") + ".docx";
        RunPowershell(
          _strBaseDirectory + @"Powershell\ExportTestResult.ps1 " + "' -Outfile " + strOutFile);
        break;
      default:
        break;
    }
    Download("~/DownLoad/" + new FileInfo(strOutFile).Name);
  }
  catch (Exception ex)
  {
    //log   
  }  
}

private void Download(string strFilePath)
{
  if (new FileInfo(Server.MapPath(strFilePath)).Exists)
  {
    Response.ContentType = "application/octet-stream";
    Response.AppendHeader("Content-Disposition", "attachment; filename=" + new FileInfo(strFilePath).Name);
    Response.TransmitFile(Server.MapPath(strFilePath));
    Response.End();
  }
} 

private int RunPowershell(string strArguments)
{
  try
  {
    var p = Process.Start(
      "powershell.exe",
      @strArguments
    );
    p.WaitForExit();
    return p.ExitCode;
  }
  catch (Exception ex)
  {
    throw (ex);
  }
}

Powershell\ExportTestResult.ps1 中：

#For debugging, all the suspected cmdlets and COM reference operations have been removed one-by-one. 
#The latest and entire content(identical to my local one)， I copy here

param ($Outfile)
cls

cp "d:\wwwroot\site\download\template.docx" $outfile
exit

我尝试过：

1. 当 asp/ps1 发布到 IIS 并从浏览器触发时，
   1. ExportTestResult.ps1 已使用新进程 ID 启动；
   2. 文件（参考ExportTestResult.ps1中的$outfile）已创建；
   3. powershell进程保持运行而不退出。
   4. 当我在Windows ProcessManager中杀死powershell进程时，浏览器立即显示下载进度
2. 当asp project/ps1直接在VS中运行时，ExportTestResult.ps1和p.WaitForExit()直接退出。

环境：

• IIS: 10
• PowerShell: 5.1

那么，如何让powershell进程在IIS中像在VS中调试一样正确退出呢？我的 IIS 配置有问题吗？

如果我错过了什么，请告诉我。