No computer can detect my Mega 2560 R3

Using Arduino IDE 1.x
1

I've tried different USB cables, computers, ports and none of them can detect my possibly bricked Mega 2560 R3. Nothing shows up at all in the Device Manager, not even "Unknown Device".

When the board is plugged in via USB, the "L" LED is constantly lit as well as the "ON" LED next the reset button.

I came up on this article here and I gave it a try, which I believe is putting it in DFU mode. However I'm not having any luck with this. Fixing Linux firmware issues on Arduino Mega 2560 | Wayne and Layne

Any one have any ideas on where to go from here? I'm very new with Arduino.

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Is it new or did you use it for a while before it became broken?

3

mart256:
Is it new or did you use it for a while before it became broken?

Been using it for awhile. I was doing some probing with my multimeter until I shorted something and sparks flew. From then on, the USB has stopped working. I have a feeling I may have fried something but I don't see any physical damage.

4

Electronic damage cannot be seen unless you open the chip.
Try uploading code through ISP to atmega2560.