The load problem of Collada dom

[Artist zhou]

hello to all of you:
I got the lib of collada dom by vs2008 today ,and I am happy.But when I used it I became upset.So I need your help;
I want to learn collada ,so I find the code in this site;

#include "stdafx.h"
#include <dae.h>
#include <dom/domCOLLADA.h>

int main(int argc, char* argv[])
{
	printf("Hello World!\n");

	DAE dae;
	daeElement *root = dae.open("simple.dae");
	if (!root)
	{
		printf("Document import failed.\n");
		return 0;
	}
	
	daeElement *node = root->getDescendant("node");
	if (!node)
	{
		printf("No nodes found\n");
	}
	else
	{
		printf("node id:%s",node->getAttribute("id"));
	}
	
	return 0;
}

But it can not work ,I find

daeInt daeIOPluginCommon::read(const daeURI& uri, daeString docBuffer)
{
    // Make sure topMeta has been set before proceeding
    if (topMeta == NULL)
    {
        return DAE_ERR_BACKEND_IO;
    }

the topMeta is NULL;
If you kown I will very grateful?

[Artist zhou]

Now I know it's The collada dom problem ,I change other collada dom ,it work fine.