QtMultimediaKit on Windows 7 error

[A Former User]

I install QtMobility on winddows 7 for QtSDK (Qt 4.8.1), but when I try to use the QtMobility elements from qml in desktop application i get this error:
defaultServiceProvider::requestService(): no service found for - "com.nokia.qt.mediaplayer"

this is part of my qml code:

@import QtQuick 1.1
import QtMultimediaKit 1.1
Rectangle
{
width: 500
height: 500
Video
{
id: vid
width: 400
height: 400
source: "C/MVI.AVI"

}
MouseArea
{
    anchors.fill: parent
    onPressed: vid.play()
}

}
@

any idea what is wrong here?