[2005] set app.config value

[jlbantang]

is there a missing line why the new values were not save to app.config?

<?xml version="1.0" encoding="utf-8" ?>
<configuration>  
  <appSettings>
    <add key ="defaultuser" value ="Test"/>
    <add key ="defaultpass" value ="1234abcd"/>
  </appSettings> 
</configuration>

ConfigurationManager.AppSettings.Item("defaultuser") = userNameTextBox.Text.ToString
        ConfigurationManager.AppSettings.Item("defaultpass") = passwordTextBox.Text.ToString