I was working with Arduino in Win 8.1, when suddenly it stopped work. I tried to reinstall the drivers and IDE several times, but it didn't solved. 

In Win 8.1, when I plug the arduino, I get the pop up message:

USB Device Not Recognized in Windows

Also, when I try to upload a sketch, I get this error in Arduino IDE:

    avrdude: ser_open(): can't open device "\\.\com5": the system cannot find the file specified

I switched to Linux (Debian Jessie 64 bits), but it also doesn't get recognized, and I getting the same error, only the port Is different.

I am guessing is a problem with avr, but I don't know what can I do about it. 

Other  symptoms:

- In both systems the port tool in IDE is grey, so I can't choose a port.

- When I press the reset button in Arduino, nothing happens.

- The led L (13) is constantly shinning. It never blinks or stops.

Solutions I tried:

- Reinstall drivers
- Modify the preferences.txt file to change the COM port
- Fall back to a previous IDE version
- Change the usb cable