plugin cannot be loaded for module "Qt3D": Cannot load library

Hi,

I can not run the qml 3d example "basket.qml" which is available at http://doc.qt.nokia.com/qt3d-snapsho...-examples.html

My step is
1) following the build step http://doc.qt.nokia.com/qt3d-snapsho...-building.html
2) build the qt3d source codes C:\Qt\4.7.1-VS\qt3d\src\imports\threed, then qthreedqmlplugin.dll created in local release dir.
3) copy the release dir to C:\Qt\4.7.1-VS\qt3d\src\imports\threed\Qt3D, and copy baskket.qml to there either.
4) put file qmldir with "plugin qthreedqmlplugin" under "C:\Qt\4.7.1-VS\qt3d\src\imports\threed\Qt3D"
5) invoke qml using "qmlviewer -I . basket", but nothing happened , inqmlviewer's warning message:

it shows:

file:///C:/Qt/4.7.1/qt3d/src/imports/threed/basket.qml:43:1: plugin cannot be loaded for module "Qt3D": Cannot load library C:/Qt/4.7.1/qt3d/src/imports/threed/Qt3D/qthreedqmlplugin.dll: The specified module could not be found.
import Qt3D 1.0
^

Very confused why this failed. Just put some snapshots for your better understanding what I did.

David Chang