WinHttpRequest ResponseText为文本（.txt）文件变空 - Windows2008R2 / Windows 7

Question

我是QTP和VBScript的新手，我正在尝试将文本文件内容作为响应（示例网址：http://x.x.x.x/dir/MIS/test_667/logfile.667.txt）。以下代码在WindowsXP上按要求工作，但在Windows7 / Windows2008R2上获取'Empty'ResponseText（sIMPResponse = objWinHTTP.ResponseText）。

我尝试使用不同的用户代理字符串@ http://www.zytrax.com/tech/web/msie-history.html，但没有运气。

任何人都可以协助解决方案获取WinHTTP.ResponseText的.txt文件内容。

提前感谢您的帮助。

CodeSnippet：

    Dim sResponse, sIMPResponse

    Function PortalUrlExists(ByVal sUrl)
    On Error Resume Next
    UrlExists = False
    Dim objWinHTTP, nStatus
    'Create a WinHTTP Request using the link's URL
    Set objWinHTTP = CreateObject("WinHttp.WinHttpRequest.5.1")
    If Err.Number <> 0 Then
     Exit Function
     End If
     objWinHTTP.Open "GET", sUrl, False
     objWinHTTP.SetRequestHeader "User-Agent", "Mozilla/4.0 (compatible; MyApp 1.0; Windows NT 5.1)"
     'Send the Request to the Server and capture the response
     objWinHTTP.SetTimeouts 180000, 180000, 180000, 180000
     objWinHTTP.Send 
     If Err.Number <> 0 Then
      Set objWinHTTP = Nothing
      Exit Function
     End If
     nStatus = objWinHTTP.Status
     If nStatus = 200 Then
       UrlExists = True
      If InStr(1, sUrl, ".txt", vbTextCompare) > 0 Then
       sIMPResponse = objWinHTTP.ResponseText  ' ***** This is getting "Empty", where as it has to get the text file content from the URL ****
      Else sResponse = objWinHTTP.ResponseText
      End If
     End If
     Set objWinHTTP = Nothing
    End Function