Windows 2003 "forgets" USB External Hard Drive

Our church has a DELL server running Windows 2003/64-bit. We have an
external hard drive for backups, etc... The server is set to update the
patches automatically. After the last set of patches, the server failed and
the clients could not access any of the shares.

We found that the problem was Active Directory did not build correctly.
When the reboot took place, the external USB hard drive was not recognized.
We rebooted the server, and saw the server 'tapping' the external drive, and
we heard it click, again, and again, and again... Finally, we unplugged it,
and Active Directlry completed and everything works fine. Did a nice job of
rebuilding the indices... 8^)

Is there a problem with Windows 2003/64-bit and USB drives? I've seen some
posts about race conditions.

I have a personal external USB drive, for my XP Pro system, a Compaq, at
home, and I can't boot that PC with the USB connector plugged in. The system
just 'sits'...

The fact that I see this on different vendor hardware leads me to think this
is a software issue...

Anyone ever see this?