<appSettings>
  <add key="productspagedesc" value="TODO: Edit this default message" />
  <add key="servicespagedesc" value="TODO: Edit this default message" />
  <add key="contactspagedesc" value="TODO: Edit this default message" />
  <add key="aboutpagedesc" value="TODO: Edit this default message" />
  <add key="homepagedesc" value="TODO: Edit this default message" />
 </appSettings>

Dim myConfiguration As Configuration = System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration("~")
        myConfiguration.ConnectionStrings.ConnectionStrings("myDatabaseName").ConnectionString = txtConnectionString.Text
myConfiguration.AppSettings.Settings.Item("myKey").Value = txtmyKey.Text
myConfiguration.Save()