Help My Melzi board stopped communication.

Hi i just got my reprap from reprappro and i built it.I printed a few thing and they came out fine but then when i plugged by laptop into it this morning there was to red light and i couldn't connect to it.I tried on my windows laptop and it make the sound as if it recognises it being plugged in but cant connect to it.just tried connecting it using Arduino and cant see it there ether
It melzi board running 1.0.1
Any help would be great.