This is from the Handbook page for the local file system.
Warning
The USB drive will only re-appear when all file handles are closed in your program, or the microcontroller program exits.
If a running program on the mbed does not exit or does not release it's open file handles, you will no longer be able to see the USB drive when you plug the mbed into your PC. To allow you to see the drive again (and load a new program), use the following procedure:
Unplug the microcontroller
Hold the reset button down
While still holding the button, plug in the microcontroller. The mbed USB drive should appear.
Keep holding the button until the new program is saved onto the USB drive.
My mbed USB is not working. I want to copy the binary file to mbed. May I know how can I do this now? I can use flash magic, but I dont know if it removes localfilesystem. My program stores a file in localfilesystem and reads it later. So I need localfilesystem.
Reason why USB is not working: mbed was powered ON using a baseboard that supplies 12V to mbed VCC pin. Simultaneously, I connected I connected mbed to PC via USB. USB is not working now. The program in mbed is working fine without any problem.
I want to reprogram the mbed now and I want to use localfilesystem partition in my program.