is there any problem the way i use ccomsafearray?

i have a project written in vc2005(activex)
there is an interface method like this

HRESULT getChildren([in] VARIANT vParent, [out, retval]VARIANT
*pvChildren);

the implementation code something like this:
CMyImpl::getChildren(VARIANT vParent, VARIANT *pvChildren)
{
CComSafeArray<VARIANT> arrChildren;
CComPtr<IMyElementInterface> spElem;

//loop:
.... //get element interface pointer;
arrChildren.Add(CComVariant(spElem));
//end
CComVariant vt(arrChildren);
vt.Detach(pvChildren);
return S_OK;
}

there is a wierd problem :
i could run the program in IDE (press F5),but if i double click it in
explorer to run it, it alerts me an error.

which locates in
microsoft visual studio 8\vc\atlmfc\include\atlcomcli.h
line 1926:

Expression:(___atl_condVal

here is the error location:

    CComVariant(__in_opt const SAFEARRAY *pSrc)
    {
        LPSAFEARRAY pCopy;
        if (pSrc != NULL)
        {
            HRESULT hRes = ::SafeArrayCopy((LPSAFEARRAY)pSrc, &pCopy);
            if (SUCCEEDED(hRes) && pCopy != NULL)
            {
                ::ATL::AtlSafeArrayGetActualVartype((LPSAFEARRAY)pSrc,
&vt);
                vt |= VT_ARRAY;
                parray = pCopy;
            }
            else
            {
                vt = VT_ERROR;
                scode = hRes;
#ifndef _ATL_NO_VARIANT_THROW
                ATLENSURE_THROW(FALSE, E_OUTOFMEMORY); ////////////here
#endif
            }
        }

i don't know why this happens