about IAMOpenProgress

[jefflg]

my code is as following:

JIF(m_pGB->AddSourceFilter(wFile, L"UrlFilter", &m_UrlSource));
JIF(m_UrlSource->QueryInterface(IID_IAMOpenProgress, (void**)&g_OpenPrg));
IPin * pOut=NULL;
pOut= GetOutPin(m_UrlSource,1);
JIF(RenderOutputPins(m_pGB, m_UrlSource));


hr = g_OpenPrg->QueryProgress(&ltotal, &lreceive);
Why hr is failed??? I can not get the total length and download length of the file, the file url is like "mms://43.82.1.1/test.wmv" or "

http://43.82.1.1/test.wmv"