如何从USB的MTP设备拷贝文件到PC?

下面是从PC到MTP设备的拷贝代码： 
BOOL CStMtpDevice::CopyFileToMTPDevice(IWMDMDevice *pWmdmDeviceMTP) 
{      HRESULT hrMTP; 
    IWMDMStorageControl2*  pIWMDMStorageControl2=NULL; 
    IWMDMStorage*  pIStorage;  //*pIStorageFile 
//IWMDMStorageControl*  pIWMDMStorageControl=NULL; 
    IWMDMEnumStorage*  pIEnumStorage,  *pIEnumStorageFile;     ULONG  ulNumStorage,ulNumFetched; 
    pIStorage    =NULL; 
    pIEnumStorage=NULL; 
    pIEnumStorageFile=NULL; 
    hrMTP = pWmdmDeviceMTP->EnumStorage(&pIEnumStorage); 
    if  SUCCEEDED(hrMTP)  
    {  
        ulNumStorage = 1;  
        hrMTP = pIEnumStorage->Next(ulNumStorage, &pIStorage, &ulNumFetched); 
        if  SUCCEEDED(hrMTP)    
        {  
            hrMTP = pIStorage->EnumStorage(&pIEnumStorageFile); 
            if SUCCEEDED(hrMTP) 
            { 
                hrMTP  =  pIStorage->QueryInterface(IID_IWMDMStorageControl2,    
                    (void**)&pIWMDMStorageControl2); 
                if SUCCEEDED(hrMTP) 
                { 
                    LPWSTR strScrFile=L"C:\\PERSIST.BIN";//L"PERSIST.BIN";// 
                    LPWSTR strDestFile=L"PERSIST.BIN";//L"C:\\PERSIST.BIN";//                     hrMTP  =  pIWMDMStorageControl2->Insert2(  
                        WMDM_MODE_BLOCK|WMDM_CONTENT_FILE|WMDM_CONTENT_FOLDER|WMDM_FILE_CREATE_OVERWRITE,  
                        strScrFile,    
                        strDestFile,  
                        NULL,  NULL,  NULL,    
                        NULL); 
                    if (hrMTP==S_OK) 
                    { 
                        MessageBox(NULL,"It is successed","Insert2",MB_OK); 
                        return  TRUE;    
                    } 
                } 
            } 
        } 
    } 
    return  FALSE;    
} 现要实现： 
如何从USB的MTP设备拷贝文件到PC? 把strScrFile 和 strDestFile 
调换位置之后 能弹出 MessageBox(NULL,"It is successed","Insert2",MB_OK); 
但文件没拷贝到PC里