Aspire One, PXE-MOF: Exiting INTEL PXE ROM, NO OS Found! Help!

This problem has me stumped.

I have this customers laptop. Doing some changes and about to setup an external dvd burner. Also this netbook is a acer aspire one about two months old and it is running windows Vista. So the netbook is working fine sharing files across the network, browsing the internet, and other basic tasks. So anyway, I plug in the HP external dvd burner and the laptop freezes, then shows a scrambled picture and cuts off.

So I'm a little confused. I boot it back up and get this:

PXE-E61: Media Test Failure, Check Cable
PXE-MOF: Exiting INTEL PXE ROM
Operating System Not Found

Ha so at this point, I unplug all of the USB devices like the mouse and dvd burner. I reboot again and same thing. So this time I go into the limited bios options. I disable the network option and same thing. Then I go into the bios and disable all of the "USB" options. There are no "other" options and the HDD is listed so it is detecting it. I'm completely lost on this one.

Right now Im going to let it drain so the battery will reset. Ive read up on other forums about slapping it on the bottom but I haven't tried that.

Any other options or ideas? I'm lost. I only have one windows 7 OEM that I have used the license for already. I hate to have to erase and start over on this customers machine.