USB Drive Uninstalling Itself

Hey ya'll!

I hope someone has a solution to this. It's not so much a problem as it is an annoyance.

I'm using an HP Pavilion 521 running Vista Home Premium edition. I have a Seagate IDE hard drive that I'm using as storage only for MP3 files and it's connected via a USB external enclosure. The drive connects just fine and works perfectly... as long as I don't shut down or re-boot my system! That's what's driving me crazy! Every time I re-start my system, the USB drive uninstalls itself and I have to disconnect the cable and move it to another USB port. It will then re-install and works fine from that point on... until I need to re-boot.

Does anyone know if there is a way to prevent the drive from doing this? Like I said, it's not really a "problem"... just annoying as he**!

Thanks!