Port section on Arduino Software grayed out

Your board uses a micro-USB connector (according to Adafruit METRO 328 - Arduino Compatible - with Headers [ATmega328] : ID 2488 : $17.50 : Adafruit Industries, Unique & fun DIY electronics and kits). Micro-USB cables are notorious for coming in two flavours, charge-only and data/sync. I know that you said that you tried different cables but they might all have been charge-only; try one that comes with a cell phone to sync data between PC and phone.

What does windows device manager think of your board? Does a new device show up when you connect the board?

  1. If no, try other cables (see above).
  2. If yes, what are the VID and the PID of the device? That will determine which driver you need. Any yellow triangles indicating problems?