Windows脚本文件 - Microsoft JScript运行时错误：类型不匹配

Question

我正在尝试运行一个“预构建的”.wsf文件，这对我的同事来说似乎非常好。但是，我似乎得到了错误：

  

“D：\ startup.wsf（221,8）Microsoft JScript运行时错误：类型不匹配”

var QXDM;
var PortNumber = -1;
//QXDM object was created using ""new ActiveXObject( "QXDM.Application" );""
//input received from user for PortNumber and parsed
PortNumber = WScript.Arguments( 0 );
if (PortNumber != -1)
   {
       // Change the port
       QXDM.COMPort= PortNumber;  ///////LINE:221 ERROR HERE
   }

请建议。

感谢。