USB device not recognized

My computer will not recognize my Uno after it has worked properly for about a month. I did try and drive the dc motors on my robot from the 5V header on the board, so I dont know if I drew too much current and destroyed something on the board or chip itself. My computer keeps saying "one of the USB devices has malfunctuned and is not recognized." Has anyone had this problem? Tried to re-install the drivers but it says they are up to date.

Also, does anyone know an easy way to see if the chip or the board is damaged?

Also, does anyone know an easy way to see if the chip or the board is damaged?

No easy way. You most likely damaged something in or needed by the 8u2 usb serial convertor chip. While plugged into the USB can you measure for proper +5vdc being supplied to the board?

Lefty

I could read +5vdc from the header on the board and the pins on the ATmega.

erik_z: I could read +5vdc from the header on the board and the pins on the ATmega.

That's all I got. Time for a new board most likely?

Lefty

yeah I already ordered one, I guess I can take the chip from the damaged board and install on the new one to further narrow it down. My hope is that it is the chip so I can salvage the board. Anyway, thanks for suggestions.

Using one of the bare bones boarduino variants (BBB, rBBB) might be a good idea. The hardware used for uploading is separate from the board itself. Consequently these are individually replaceable as well. If used wisely (e.g. disconnecting the uploader hardware when doing 'dangerous stuff'), only the main board is potentially in danger. Much cheaper as well.