我在Visual Studio 2010中遇到了这个奇怪的验证错误,选择了HTML5验证:

这是一个验证错误(合法或Visual Studio中的错误)还是我错过了一些明显而简单的东西?
编辑:添加相关代码.
查看cshtml:
@model My.Web.ViewModels.ListVideos
@{
ViewBag.Title = "All Videos";
}
@foreach (var item in Model.Videos) {
<a href="@Url.Action("Play", "Player", new { videoId = item.VideoId })">
<img src="http://i2.ytimg.com/vi/@item.PublisherVideoId/default.jpg" alt="@item.Title" style="border: 0" />
</a>
}
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_Layout.cshtml:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>@ViewBag.Title</title>
<link href="@Url.Content("~/Content/Site.css")" rel="stylesheet" type="text/css" />
<script src="@Url.Content("~/Scripts/jquery-1.6.4.min.js")" type="text/javascript"></script>
<script src="@Url.Content("~/Scripts/modernizr-1.7.min.js")" type="text/javascript"></script>
</head>
<body>
<div class="page">
<header>
<div id="title">
<h1>My Web</h1>
</div>
<div id="logindisplay">
@Html.Partial("_LogOnPartial")
</div>
<nav>
<ul id="menu">
<li>@Html.ActionLink("Videos", …Run Code Online (Sandbox Code Playgroud)