IHTMLWindow2 execScript failed result -1073741819

hi,all
I execute javascript failed and result is -1073741819, what is the
mean?
my code is following code
///////.....get IHTMLDocument2,and get IHTMLWindow2
normally/////////////

CComQIPtr<IHTMLWindow2> spWin;
hresult = pIHTMLDocument2->get_parentWindow( &spWin );
VARIANT pvarRet = {0};
CString strSrc="javascript:var result1=func1(this);
func2(this,result1);"
hresult = spWin->execScript((_bstr_t)strSrc, //BSTR
L"JavaScript", //
&pvarRet ); //pvarRet VT_EMPTY
the strSrc is string of code not a function.


thanks in advance
victor

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