I tried to use RobotC 1.10 to download the firmware and the message log says the following:

Opening connection to NXT brick
Checking NXT battery level high enough to continue
Boot into firmware download mode
Closing any connections to NXT brick

Then I get an error message stating "Brick failed to enter boot mode". The brick starts making a clicking noise. When I try the Download Firmware command again it says "No NXT bricks connected via USB".

I have to go back to the Mindstorms NXT G software to download the NXT 1.05 firmware to get the brick back to normal.

What am I doing wrong? Anyone else having this problem?

Note: I'm running Windows XP SP2 within a Virtual Box virtual machine on my iMac running OS X 10.5.3.

Hi, I had the same problem (btw I use a virtualbox too). To solve this I pushed the reset button, downloaded the lego 1.05 firmware, then I placed the robotc firmware in the folder where NXT G software stores firmwares and I downloaded it using NXT G. Now it works perfectly.

It's because the NXT becomes a different "Device" when it enters firmware boot mode... your VM may need you to manually add this device so it will recognize it.