Reading through this thread, it looks like you had it working, you flipped your fan over, it was still working, and then it stopped. Did anything else change?
It looks like your computer can pick up the Arduino’s com port correctly (I’m using Windows 7 and it’s working fine, btw), but Easel/UGS aren’t detecting it. I wonder if somehow your grbl install got wiped out? At this point it seems like attempting to reinstall the X-Carve grbl version is worth a shot, since the other option is you need to replace your Arduino.
Here’s a link to a thread about re-flashing your Arduino, maybe it will help: