A few weeks ago I built my own Arduino Micro. Everything worked fine and it connects every time. I have built a second one, with the exact same processor schematic as the first one. It turns on, and I was able to bootload it with an Arduino Uno, just like the first one. But it will not connect to my computer.
When I plug it into my PC, the lights flash on but I get nothing. It does not show up in device manager anywhere, and its like I plugged nothing in, in the first place.
When I plug in my other Arduino Micro it works fine. But this one does not. I have tried switch PCB's (maybe the first one was bad) but nothing seems to work. I have even switched the ATMega32U4, but I still get the same issue.
When I connect my multimeter to the USB port and the corresponding D+ and D- pins on the processor, I get that there is resistance and there are no crossed connections.
I feel that at least the computer should say "Device not recognized," but I just get nothing. Is my Arduino bricked? Has anyone else had a similar problem?