I wrote a custom Windows service to deal with some file cleanup, editing, etc. In the OnStart method of this program, I have:

```
timer.Elapsed += new ElapsedEventHandler(OnElapsedTime);
timer.Interval = Convert.ToInt32(System.Configuration.ConfigurationSettings.AppSettings["RunInterval"]) * 60 * 60 * 1000);  //yeah, i know its an old method
timer.Enabled = true;

```

but the AppSettings["RunInterval"] is returning null every time, even though I have:

```
<appSettings>
    <add key="RunInterval" value="8" />
    <!-- Lots of other stuff -->
</appSettings>

```

in the .exe.config. Why is it doing this? Are the config filed not loaded until after OnStart? Seems like that wouldn't make a lot of sense.