I had the same problem but this occurred after 1 flight. PC failed to recognise USB lead and "Search" was "greyed" out so no response. All other PC USB systems checked and AOK. So returned lead and awaiting replacement. Here's hoping.
Off topic but the Manual isn't clear on whether the Tx should be switched on or not. I have the Futaba 6EXA with square adapter. I'm sure I've read somewhere that the PC powers it but it is unclear.
Any advice welcome
Regards pedall