Arduino Uno R3 stopped working - USB not recognizing the unit anymore

[system]

Hi everybody,

I need help please!

I bought an Uno R3 a couple of weeks ago and went through the entire process of getting it working. I was able to upload sketches and everything worked fine.

After returning to it this morning, after a couple of days, I am no longer able to upload sketches.

I did some searching and found nothing that pertains to my particular problem as it worked fine a couple of days ago.

When I plug it into my PC, it DOES NOT make that "windows usb connecting sound" but it does power the unit with the yellow LED blinking, then turning on and remaining on along with the green power LED. It does not connect to the PC apart from the PC supplying power to the unit.

I have tried everything I could come across, re-installing software, removing the micro-controller and connecting it again and nothing seems to work.

When I connect an external power source alone, in the form of a 9V battery, the same happens. The yellow LED blinks and then remains on along with the green LED remaining on.

Am I missing something?

Could anybody please help?

Thank you!

[narzan]

did you used RX, TX pins before ?!
make a reset for the ATmega16U ship
disconnect your arduino from everything just plugin the usb port
read this article
here
after you finished everything just upload blink sketch from the library to test it

[system]

Louis, I had a similar problem yesterday and fixed it. See my response (#3 - FredKD) under "port selection in tools is grayed out". My UNO would not upload so I had to reload my driver.

[system]

Hi Narzan, no I have not used the RX or TX pins before.

I also tried what you suggested and still no luck. Bridging those two pins had no affect.

It has also come to my attention that my Arduino is not an original as it looks slightly different to the ones on the link you sent me.

Could this be part of the problem?

I have attached pictures of my unit.

FredKD, i also tried what you suggested and also no luck.