简单的SqlCECommand更新获胜'；不起作用.为什么?

我不明白为什么这个简单的更新命令不起作用：

        private void button1_Click(object sender, EventArgs e)
    {
        SqlCeCommand cmd = new SqlCeCommand("UPDATE tbl_Settings set password = '1234')", conn);
        try
        {
            cmd.ExecuteNonQuery();
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message.ToString());
        }
    }

错误消息：There was an error parsing the query. [ Token line number = 1,Token line offset = 42,Token in error = ) ]

我的选择和插入命令完美工作：

 SqlCeCommand cmd = new SqlCeCommand("SELECT password FROM tbl_Settings", conn);
        string password = cmd.ExecuteScalar().ToString();