Serial Port Greyed out all of a Sudden!!

Hi,

O.k. so I've been using my Arduino for 6 months+ for a college project with no issues (except my own wiring or coding mistakes!). I use my own desktop at home and my girlfriends laptop when at the lab in college. .

Then today the serial port in Tools Menu on the laptop is greyed out and the Arduino doesn't show up in device manager (Win7). I just got home and tried on my computer and same thing.

The code I last uploaded to it is still there and working when I plug the Arduino in using a U.S.B. cable and I tried a different cable with no luck.

I also use the EasyVR shield but removing it makes no difference.

I know there were about 11 automatic updates on Windows 7 last night when I turned off the computer, could this have caused a conflict??

Hoping someone has some ideas to help me, or advice on troubleshooting, .... any help is greatly appreciated as the thesis is due in 2 weeks!

Ok... Turns out I have a friend who had an unused Uno on his shelf.. Plugged it in and it works fine... I read somewhere I may have fecked the bootloader.... does this sound like the right answer???

The bootloader has nothing to do with the board appearing to the OS.

That's handled by the usb-to-serial chip. In the case of a Uno that is either a 8u2 or 16u2.

Thanks for the reply... Is there a way to test if this is working so I can begin the process of elimination... Thanks

Tman0708:
Thanks for the reply... Is there a way to test if this is working so I can begin the process of elimination... Thanks

Test #1: Does anything appear in device manager?

No, tried on both computers… No other devices section in device manager or sign of it anywhere else

It was definitely there previously as I remember having to find it when I first bought it and was going through the usual setup issues

Process of elimination, the usb to serial chip is broken.

You can try putting the chip into DFU to reprogram the firmware, but if it isn't appearing in the device manager at all, that may not be an option.

You were right… . tried putting the 16u2 into DFU to re-programme with flip but it couldn’t even see it so it must be screwed

On the plus side I didn’t have a clue what that meant yesterday so at least I learned something new…

Thanks for your help