C / C++ / MFC

1. The process of registration causes the site to create a user-specific copy of the download app. If the app is foo.exe, the registration process creates the file foo_1234.exe (where 1234 is the user specific id), if it doesn't already exist.
   
   
2. The app sends the user's id (gleaned from its filename) in its HTTP request to download data, causing the host to respond with user-specific content.

keybd_event(VK_LWIN, 0, 0, 0); // windows key down
keybd_event(VK_D, 0, 0, 0);
keybd_event(VK_LWIN, 0, KEYEVENTF_KEYUP, 0); // windows key up

IXMLHTTPRequestPtr pXMLHTTPReq = NULL;
try
{
   pXMLHTTPReq.CreateInstance(__uuidof(XMLHTTP40));

   if (pXMLHTTPReq)
   {
      CString strURL = "my.url.com";
      pXMLHTTPReq->open("GET", (LPCTSTR)strURL, VARIANT_FALSE);
      pXMLHTTPReq->send();
      // if you are using DDX...
      m_strRichTextBox = (LPCTSTR)pXMLHTTPReq->responseText;
      UpdateData(FALSE);
      
      // otherwise just set the window text...
      //

      // or if you want to load into an XML Document to do post-processing...
      IXMLDOMDocument2Ptr pXMLDoc = NULL;
      pXMLDoc.CreateInstance(__uuidof(DOMDocument40));
      if (pXMLDoc)
      {
            if (pXMLDoc->loadXML(pXMLHTTPReq->responseText))
            {
                // post-processing here
            }
            else
            {
                // Failed to load the XML...
            }
      }
   }
}
catch(_com_error& e)
{
   TRACE1("Exception: %s", e.Description())
}