my classic keeps shutting down

The Munk

I'm running 10.0.4 and 9.2.1. For some reason, I can't keep the 9.2.1 open. It starts up when I turn the computer on, but for some reason it just closes. If I open a classic app, it reloads the 9.2.1 and then as soon as it's all open, it closes right up again. I have no idea why this happens. do you? I'd love to know what to do with this, thanks.