I have this annoying issue where my android google nexus one can’t run my application from a macbook pro using eclipse. It says “device not found”.
The worst thing is that it used to work most of time when I was on 2.3.3 android version, but now I get the last version (ice cream sandwich I think – 4.0.3), it is still randomly working but 3 times out of a hundred.
This is a famous issue but so far I didn’t find the solution.
I had a similar issue too and it seemed to be related to the USB hubs not working correctly. Trying resetting your PRAM and see if that helps.