对Access数据库修改一个值。提示"UPDATE 语句的语法错误"

 private void button2_Click(object sender, EventArgs e)
        {      
            OleDbConnection Conn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=\\172.16.1.13\data$\att2000.mdb");
            string SqlStr = "update userinfo set password = "11" where ssb = "30116""; 
        
            try
            {
                Conn.Open();                                         
                OleDbCommand Comm = new OleDbCommand(SqlStr,Conn);                            
                //MessageBox.Show(SqlStr);
                Comm.ExecuteNonQuery();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            finally
            {
                Conn.Close();
            }
        }