May have shorted Arduino Mega - USB device not recognized.

Hello,

So I had my arduino mega powering and bootloading an ATmega328P. Attached to this ATmega was a photocoupler to isolate.
One the isolated side I had 120VAC. Something must have shorted on this side, because the photocoupler blew up (image attached).

Now my arduino does not work with my computer. It receives power, but says USB device not recognized. Is my arduino garbage? or what can I do at this point?
I have tried a different USB port and restarting my computer.

Cheers,
Shane