my father bought my mother an Acer aspire one 532h for christmas. All of a sudden last weekend the USB ports stopped working in Windows. MP3 player not recognized, USB wireless mouse stops working. Nothing. So today I get my hands on the thing. I plug in my digital camera, boom - recognized. mouse, not so much. I try an MP3 player, no deal. I unplug and plug in my camera, not recognized. Nothing showing up in device manager. I uninstall and reinstall every USB device in device manager (which shows everything's fine) and still no change. However, when booting if a USB device is plugged in (i.e. the mouse) the machine just sits and won't boot (not booting to the USB drive, just sits and pauses until the device is removed).
I've flashed the bios, I've reset the bios to factory defaults (not that my parents played with the bios, but thought what the heck). No deal. I did what Acer apparently calls a reset, which is pull the battery, unplug the A/C adapter, and hold the power button. no deal.
From what I've read, it seems to be a common thing for Acer machines (Especially netbooks) and the workaround seems to be get a usb card. Well, the netbook only has a PCMCIA express slot. From what I've read, Acer support says send it to them, and they reinstall the OS. From what I read, it fixes the problem for a few weeks. The OS is Windows 7.
This is likely a hardware issue, and could be considered a defect. If it was purchased from a local retailer like Best Buy, with a service plan you could convince them to just swap it out with another, without one maybe you could be stubborn but kind and talk to a manager... they'll usually make an exception and help you out.
Without replacement, if the laptop has more than one USB port, maybe try using just one or the other, it could be limited to just one. If not, you'll probably have to go through the proper channels with Acer and convince them it's a hardware/defect issue. They'll eventually replace it, but with any luck you won't have to send it in more than once for them to give in and do it.
A long shot would be to purchase an external USB hub, possibly with it's own power supply. Maybe that would handle the grounding initially and allow the other devices to work.
Good luck ;)