Uno R3 unable to load sketches or bootloader


Apologies in advance for posting what I’m sure is a daily occurrence on here. However I’m on day 3 and I’ve exhausted every thread, blog and troubleshooting guide I could find. I’ve attached my verbose log during compile and upload for reference. I have an Arduino Uno R3 with a ATMEGA328P chip. I’ve tried to upload on three different computers now with no luck. I tried a windows 8 with the signature enforcement disabled, a Windows 7 and a Mac OsX, as well as a windows 7 on bootcamp on a Mac (same computer). I’ve installed the driver as well as manually ensuring it was installed using the hardware manager, I’ve confirmed that the Uno is being registered on a com channel and that the IDE is using the correct COM channel, has the correct board selected and have tried doing this in AVRISP, AVRISP MkII and Arduino ISP.

I’ve tried hitting the reset button before hitting upload, after, counting at various intervals between 1 and 10 seconds before and after upload, holding reset, unplugging and replugging the cable in during upload. I’m honestly unsure of what else to try. I’m reasonably certain the chip is working because when I hit reset the light does turn on and then blink after. I see the RX light blinking when upload is active but I get the exact same error messages on every set up, I’ve even tried using different USB cords.

It won’t let me burn the bootloader again either, it keeps giving me a device “USB” not recognized error. I know it’s not the program because I’ve checked it character for character against the examples (blinking LED) and I program in C for a living. I’m just not sure what else to check at this point.

UnoErrorLogVerbose.txt (21.3 KB)

Have you tried burning a new boot loader?

Yes, as I stated in my original post “It won’t let me burn the bootloader again either, it keeps giving me a device “USB” not recognized error”

I’ve attached the exact error message I’ve been receiving. I’m unsure of what to do at this point. I’ve seen other people receiving this error but it’s often fixed with a driver reinstall or some of the same steps I’ve tried up until this point. Again, I don’t think the chip is bad because the reset switch behaves as I expect but I’m unsure of what else to try. I am using the latest version of the IDE, 1.6.5

UnoBootloaderError.txt (765 Bytes)

What did you use to burn the bootloader originally?

Forgive me, I was under the impression the Uno had one burned into it on delivery. The various set up guides I looked at only advised to burn a bootloader if the other steps had not worked (such as my case). So I haven't. I've heard you can burn a bootloader from the command line, which I'm fine with doing but I'm uncertain if I need to use a different way of connecting other than the USB a-b cables. Particularly since I'm confused about the error I'm receiving (which I've received on all computers I've tried it on) upon attempting to burn a bootloader.

In the meantime I've been looking at this: for burning a bootloader. Does the command line option seem like something I should pursue and can this be done from the USB cable I've been doing or do I need to know more? If anyone has a step by step guide for manually burning a bootloader onto an Uno I'd love to see it.

You burn bootloaders via the ICSP header. Try this method if you have a 2nd uC board.

If you don't, you need to get one, or get a programmer.

Link added this time:

Ok, this definitely sounds like the piece I'm missing. Thank you very much CrossRoads, I'm going to pick up a programmer ( and I'll get back to you once I have it in hand to let you all know how it went.