Ajax.beginForm 이 작동하지 않을때

VS2013 기준 TOOLS > NuGet PakageManager > Manage NuGet Pakages for Solution... > Installed pakages 에서 "Miscrosoft jQuery Unobtrusive Ajax " 설치 유무 확인하세요. 없으면 Online 탭에서 검색 후 설치하세요.
BundleConfig.cs

public class BundleConfig
{
    // For more information on bundling, visit http://go.microsoft.com/fwlink/?LinkId=301862
    public static void RegisterBundles(BundleCollection bundles)
    {
        bundles.Add(new ScriptBundle("~/bundles/jquery").Include(
                    "~/Scripts/jquery-{version}.js"));

        bundles.Add(new ScriptBundle("~/bundles/jqueryval").Include(
                    "~/Scripts/jquery.unobtrusive*",
                    "~/Scripts/jquery.validate*"));

        // Use the development version of Modernizr to develop with and learn from. Then, when you're
        // ready for production, use the build tool at http://modernizr.com to pick only the tests you need.
        bundles.Add(new ScriptBundle("~/bundles/modernizr").Include(
                    "~/Scripts/modernizr-*"));

        bundles.Add(new ScriptBundle("~/bundles/bootstrap").Include(
                    "~/Scripts/bootstrap.js",
                    "~/Scripts/respond.js"));

        bundles.Add(new StyleBundle("~/Content/css").Include(
                    "~/Content/bootstrap.css",
                    "~/Content/site.css"));
    }
}

BundleConfig.cs 에서 jqueryval 에 넣었으면

@Scripts.Render("~/bundles/jqueryval")

구문 Index.cshtml 에 추가

Index.cshtml

    @Scripts.Render("~/bundles/jquery")
    @Scripts.Render("~/bundles/jqueryval")

    @using (Ajax.BeginForm("GetList", "Master", FormMethod.Post, new AjaxOptions { HttpMethod = "Get", InsertionMode = InsertionMode.Replace, UpdateTargetId = "dataGrid" }, new { id = "search_form" }))
    {
        <input type="hidden" name="page" value="1">
        <!-- 첨삭 센터 선택 시작-->
        <div class="panel panel-default">
            <div class="panel-body">
                <div class="form-group-sm">
                    <label for="SchoolSelect" class="col-lg-2 control-label hidden">선택</label>
                    <div class="col-lg-10">
                        <select class="form-control input-group-sm" id="SchoolSelect">
                            <option value="" selected="selected">첨삭센터를 선택하세요.</option>
                            <option value="1">1</option>
                        </select>
                        <button class="btn btn-default" type="submit">검색(ajax)</button>
                    </div>
                </div>
            </div>
        </div>
    }
    <hr>
            <div class="form-group-sm" id="dataGrid">
                @Html.Partial("AssignDataList")
            </div>

PartialView 인

AssignDataList.cshtml

@{
    Layout = null;
}
@{
    if (Model != null)
    {

        var grid = new WebGrid(
        canPage: true,
        rowsPerPage: Model.PageSize,
        canSort: true,
        ajaxUpdateContainerId: "grid");

        grid.Bind(Model.Content, rowCount: Model.TotalRecords, autoSortAndPage: false);

        grid.Pager(mode: WebGridPagerModes.All
        , firstText: "처음"
            //,previousText :  "이전"
            //,nextText : "다음"
        , lastText: "마지막"
        , numericLinksCount: 5
        );

        grid.GetHtml(htmlAttributes: new { id = "grid" },   // id for ajaxUpdateContainerId parameter
            fillEmptyRows: false,
            tableStyle: "table table-striped table-hover ",
            headerStyle: "webgrid-header",
            footerStyle: "webgrid-footer",
            alternatingRowStyle: "webgrid-alternating-row",
            selectedRowStyle: "webgrid-selected-row",
            rowStyle: "webgrid-row-style",
    //mode: WebGridPagerModes.All,
            columns: grid.Columns(
            grid.Column(header: "선택", format: @<text><input type="checkbox" name="cbSelectbox" value=""></text>),
            grid.Column("SchoolCode", "학원코드"),
            grid.Column("School", "학원"),
            grid.Column("BR", "BR"),
            grid.Column("WR", "WR")
        )
        );
    }
}