使用框架怎么退出系统？？？
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=gb2312" /><title>无标题文档</title></head><frameset rows="80,*" cols="*" frameborder="no" border="0" framespacing="0"> <frame src="head.aspx" name="topFrame" scrolling="No" noresize="noresize" id="topFrame" title="topFrame" /> <frameset cols="170,*" frameborder="no" border="0" framespacing="0"> <frame src="menu.aspx" name="leftFrame" scrolling="No" noresize="noresize" id="leftFrame" title="leftFrame" /> <frame src="main.aspx" name="main" id="main" title="main" /> </frameset></frameset><noframes><body></body></noframes></html>
<HTML><HEAD><META http-equiv=Content-Type content="text/html; charset=gb2312"><LINK href="css/admin.css" type="text/css" rel="stylesheet"></HEAD><BODY><form runat="server"><TABLE cellSpacing=0 cellPadding=0 width="100%" background="images/header_bg.jpg" border=0> <TR height=56> <TD width=260><IMG height=56 src="images/header_left.jpg" width=260></TD> <TD style="FONT-WEIGHT: bold; COLOR: #fff; PADDING-TOP: 20px" align=middle>当前用户：<asp:Label ID="lblName" runat="server" Text=""></asp:Label> <A style="COLOR: #fff" href="" target=main>修改口令</A> <asp:LinkButton ID="lkbtnExit" runat="server" style="COLOR: #fff" onclick="lkbtnExit_Click" target="_self">退出系统</asp:LinkButton> </TD> <TD align=right width=268><IMG height=56 src="images/header_right.jpg" width=268></TD></TR></TABLE><TABLE cellSpacing=0 cellPadding=0 width="100%" border=0> <TR bgColor=#1c5db6 height=4> <TD></TD></TR></TABLE> </form> </BODY></HTML>后台： protected void lkbtnExit_Click(object sender, EventArgs e) { HttpCookie cookie = Request.Cookies["Adminuser"]; cookie.Expires = DateTime.Now.AddDays(-10); Response.Cookies.Add(cookie); Server.Transfer("login.aspx"); }可是当我点击退出的时候，框架不退出，就head.aspx没了！还有退出过后，我点击Index.aspx页面，左边的menu.aspx和login.aspx一起出现了