sure ... :) .. i made some minor changes for better performance , hope you wont mind. :) try below:

LOGIN PAGE:

SqlConnection cn=new SqlConnection("Data Source=.\\SQLEXPRESS;AttachDbFilename=|DataDirectory|\\test.mdf;Integrated Security=True;User Instance=True");
            cn.Open();
          
            string name = txtname.Text;
            string password=txtPasswd.Text;           

            SqlCommand cm =new SqlCommand("Select COUNT(*) FROM login WHERE name=@name and password=@password",cn);
            cm.Parameters.Add("@name", SqlDbType.VarChar).Value = name;
            cm.Parameters.Add("@password", SqlDbType.VarChar).Value = password;
 
            int count=(int) cm.ExecuteScalar();
            cn.Close();
            if (count > 0)
            {
                Session["test"] = name;
                Session["user"] = Convert.ToString(Guid.NewGuid());
                Response.Redirect("welcome.aspx");
            }
            else
            {
                Response.Write("login failed");
            }

                      

WELCOME PAGE:

 protected void Page_Load(object sender, EventArgs e)
        {            
          if (Session["user"] != null && Session["test"] != null)
            {
                // let them access the page.
                lblName.Text = "Welcome " +Session["test"].ToString();
            }
            else
            {
                //clear the cache and  redirect back to login page.
                Response.Cache.SetExpires(DateTime.UtcNow.AddMinutes(-1));
                Response.Cache.SetCacheability(HttpCacheability.NoCache);
                Response.Cache.SetNoStore();
                Session.Abandon();
                Response.Redirect("login.aspx");
            }
        }

WEB.CONFIG:

<configuration>
  <system.web>
     <sessionState timeout="1"></sessionState>
  </system.web>
</configuration>