A customer wanted me to find out why his PC would sometime not start when his external USB drive (a 160 GB Maxtor) was connected. Unplugging the drive would always fix the problem.

I’m also asked to do a few other housekeeping tasks. During my time there, I could not find a problem with restarting the PC… I tried about 6 times.

So I ask the customer to keep an eye on it.

Sure enough, 2 days later, the problem is back.

So I return, and I see that the PC is failing to start (the bios gets as far as displaying “searching for usb devices” and then just sits there, frozen.

I look at the bios, but its set to boot CDrom first, hdd second, usb drives last (I had checked this the first time around as well)

I follow the wiring:

The usb drive has its own power supply (which doesn’t seem to be overheating).

The drives usb cable goes to an unpowered usb hub… Hmmm. unpowered hubs can sometimes be a problem…

The hub has a usb flash drive, and the maxtor external drive connected, so it shouldn’t be a problem.

Call me paranoid, but I decide to plug the maxtor directly into a free usb port on the PC itself.

Once I did that, the problem was solved.