使用Mozilla扩展名执行.jar文件

我看了这里回答的以下问题:

How to open file in Mozilla Add-on SDK using system default application

How can I open an external app from Firefox addon? (Eg: default text editor)

Perfom a ShellExecute from Firefox Addon

然而,这些解决方案中没有一个对我有效,我觉得问题可能比我最初想象的更严重。本质上,我正在尝试使用Mozilla插件扩展名启动.jar可执行文件。我的代码如下所示:

var buttons = require('sdk/ui/button/action');

var button = buttons.ActionButton({
  id: "execute-jar",
  label: "Download Report",
  icon: {
    "16": "./icon-16.png",
    "32": "./icon-32.png",
    "64": "./icon-64.png"
  },
  onClick: handleClick
});



function handleClick(state) {
    // try {
        // var file = Services.dirsvc.get("Desk", Ci.nsIFile);
        // file.append("C:\Users\QaziWa\DownloadReportPPE.jar");
        // file.launch();
    // }
    // catch (ex) {
        // console.error("failure");
      // Failed to launch because e.g. the OS returned an error
      // or the file does not exist,
      // or this function is simply not implemented for a particular platform.
    // }

    let {Cc, Ci} = require('chrome');
    var file = Cc["@mozilla.org/file/local;1"].createInstance(Ci.nsILocalFile);
    file.initWithPath("C:\Users\QaziWa\DownloadReportPPE.jar");
    console.log(file);
    if(file.exists()){
        file.reveal();
        file.launch();
    }
    else {
        console.log('Failed.');
    }
}

由于某种奇怪的原因,我的.jar文件没有被检测到,我无法理解为什么。我希望有人能提供任何意见,说明为什么会这样。