[web developer 2010 express]The background image is missing when debugging

When debugging the webpage, the background didn't come out. How can i solve this problem? Thank you very much.
body
{
    background-color: #000000;
    font-size: .85em;
    font-family: "Trebuchet MS" , Verdana, Helvetica, Sans-Serif;
    margin: 0;
    padding: 0;
    color: #696969;
    background-image: url('../App_LocalResources/Webpage/Opera-Background-Wood.jpg');
}



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