I bought my Uno a couple years ago however recently (past couple weeks after sitting idle for maybe 3 months) I have been having trouble uploading sketches.
They sketches verify fine so that leads me to believe its the communication between the board and my laptop. (using a regular usb to connect them)
Below I will attach screen shots of the error messages but I have looked for solutions already,
I have:
Uninstalled and reinstalled the Arduino IDE
Changed the usb cable I was using
checked for driver updates
made sure it was connected to the correct board & port
Tried the trick with resetting while uploading
and even bought a replacement ATMEGA328P chip from Atmel
all to no avail.
when trying to load new sketches I only have the usb plugged in so there shouldn't be a problem with the TX/RX pins being occupied, the green ON light is on constantly and orange light near the ground pin is on, sometimes flashing sometimes solid, however neither the TX or RX lights ever flash.
Also I tried the new web editor but when trying to connect to the board it grays out the upload button but displays the notification that it is now connected (see attached)
Also also, when connected to power, my uno (with original chip) still supplies 3.3v, 5v and ground still works and also PWM pins 9-11 are live. I believe this to be from the last sketch I successfully uploaded (RGB LED colour cycle) but the sketch isn't running because when i connect an RGB LED, it doesnt cycle and supplies the full resulting in white light from the LED which was never in the sketch.
Hopefully someone can help, apologies in advance for if it was something trivial I have overlooked.
Nathan
arduino error message.txt (32.1 KB)
Verification of a sketch does not check the status of the connection between the board and the computer.
You are on the wrong track with that assumption i'm afraid.
Does the board show in "device manager" (assuming windows as there is a lack of detail)
If it does not show there you have a primary issue possibly with drivers (unknown if its a clone or the real deal)
Maybe type of USB port is at fault (unknown type of USB)
Cover those bits first.
Yes windows, shows in device manager.
only used second chip to check if first one was fried, all details pertain to the uno as it came from factory.
as for type of usb, its just the usb B from board to type A in laptop
USB 1.0 2.0 3.0 ?
repeated "If it does not show there you have a primary issue possibly with drivers (unknown if its a clone or the real deal)"
I have seen problems with serial downloads when plugged into USB3 port on laptop.
Try confirming what your laptop has, and make sure to use a USB2 port.
okay so, i did have it plugged into the usb 3 port but just tried it with usb 2 and still no progress.
with regards to "If it does not show there you have a primary issue possibly with drivers (unknown if its a clone or the real deal)" in device manager it shows up as Arduino Uno COM3 under 'Ports (COM & LPT) and no mention under usb controllers
Ok showing up as an actual UNO in device manager is usually a good indication of a real Arduino. (no extra drivers req.)
It would also be a good indicator that the USB chip itself is probably good.
If you have anything connected to the board then remove it (including any aux power to the power socket)and try an upload again eg Blink or BareMinimum.
Also do not use USB 3.0 cables either (as well as USB 3.0 ports). Right now I have 3 USB 3.0 cables that work fine on the target devices they came with and other USB 3.0 items but not with most of my Arduinos.
We cant tell from here but do you have any other software that may be blocking or intercepting the com ports ?
Also as a simple test try turning off any additional antivirus / security software.
BTW I cannot see an error on your web editor pic. If you upload (or try) in CREATE then there is the option there at the far right to copy any messages out so that you can post them up too but turn on verbose in the editor preferences first.
the error I was referring to in CREATE was a red herring anyway, it was because I hadn't downloaded the plugin necessary now I have and I get the same error message when using the IDE.
With regards to blocked ports, I have tried again to upload a sketch with my antivirus disabled again to no avail. I changed the COM port from COM3 (which to my knowledge it has always been) to various different ports and tried to upload with the same end result. when changing the port the only on that said it was in use was COM4, so Im not sure if COM3 is actually being intercepted or not.
But the location of "Arduino (COM3)" shows as Location 0 (Port_#0004.Hub_#0001) which I tried to find the PID value for using netstat in the command line in an effort to close the corresponding process but again nothing has worked.
I am appreciative of the continuing support on this thread!
All the basic things seem to have been covered.
Do you have the ability (long shot) to re-flash the bootloader ?
Side thought..Check what windows update has installed in the last fe months and look for any hardware related items and roll those back one by one with restarts between.
Take note of each one so you can put it back in if it doesnt help the issue.
I can't reflash it right now, maybe in a month or so.
I thought it would be worth seeing if I can upload sketches from my Raspberry Pi figuring that it should be able to work in the short term while I figure out exactly what was wrong with it however I have just tried to upload Blink to test from the Pi and I get the same error message as before.
hopefully this might narrow the problem down at least a little bit
will start working on rolling back drivers soon when I have a bit more time
Have you tried the loopback test?
just tried loopback test, failed, no lights flashed and nothing was returned in the serial monitor
Another update, I bought a cheap arduino nano on ebay and plugged it in, works perfectly on the IDE
Clones have been supported for quite some time and are a welcome surprise to a lot of people.
The original Nano uses a different USB chip 
The clone might even use another one again.
