# I once used Arduino Uno as a HID, and I can't turn it back to normal Arduino. **URL:** \ **Category:** IDE 1.x\ **Created:** [April 2, 2017, 11:48am UTC](https://forum.arduino.cc/t/i-once-used-arduino-uno-as-a-hid-and-i-cant-turn-it-back-to-normal-arduino/449275 "2017-04-02T11:48:17Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![pineappleman](https://avatars.discourse-cdn.com/v4/letter/p/a5b964/32.png) [@pineappleman](https://forum.arduino.cc/u/pineappleman)\ **Post date:** [April 2, 2017, 11:48am UTC](https://forum.arduino.cc/t/i-once-used-arduino-uno-as-a-hid-and-i-cant-turn-it-back-to-normal-arduino/449275/1 "2017-04-02T11:48:17Z")
I once turned my Arduino into a USB device(HID?) to use Arduino Uno as a keyboard. [http://blog.naver.com/msyang59/220064215723](http://blog.naver.com/msyang59/220064215723) I followed the instructions on the page above(The contents on the page are written in Korean since I am Korean...). I installed dfu-programmer software and uploaded the keyboard firmware on Atmega16U2. And now I want to turn it back to normal. The page above says I should just erase the dfu-programmer software from the folder where it is. But since I am not using the computer which I used to upload the software and keyboard firmware, I can't erase the software properly. I think now I erased the keyboard firmware and dfu-programmer software from the device manager. But now, I think the computer doesn't recognize Arduino. I reinstalled the IDE and Arduino driver, but I can't find anything different in the device manager. What should I do? ![asdf.png](https://europe1.discourse-cdn.com/arduino/original/4X/9/9/4/994222e2e056e057dc875a1dd8fb4c6ced3e5a3e.png) ![asdfasdf.png](https://europe1.discourse-cdn.com/arduino/original/4X/8/4/3/843aae4aab60f1299bbd0df646df343d20002b16.png) ---
**Author:** ![pert](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/pert/32/217111_2.png) [@pert](https://forum.arduino.cc/u/pert)\ **Post date:** [April 2, 2017, 11:56am UTC](https://forum.arduino.cc/t/i-once-used-arduino-uno-as-a-hid-and-i-cant-turn-it-back-to-normal-arduino/449275/2 "2017-04-02T11:56:30Z")
I don't have experience with doing this but you should be able to find the original firmware that was on the ATmega16U2 in the Arduino IDE installation folder at hardware/arduino/avr/firmwares/atmegaxxu2. Once you flash the ATmega16U2 with that firmware it should start working again as usual. ---
**Author:** ![pineappleman](https://avatars.discourse-cdn.com/v4/letter/p/a5b964/32.png) [@pineappleman](https://forum.arduino.cc/u/pineappleman)\ **Post date:** [April 2, 2017, 12:04pm UTC](https://forum.arduino.cc/t/i-once-used-arduino-uno-as-a-hid-and-i-cant-turn-it-back-to-normal-arduino/449275/3 "2017-04-02T12:04:32Z")
> pert: > Once you flash the ATmega16U2 with that firmware it should start working again as usual. Um... How can I flash ATmega16U2 with the firmware? I am not familiar with these kind of things... can you tell me how should I flash it? ---
**Author:** ![pert](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/pert/32/217111_2.png) [@pert](https://forum.arduino.cc/u/pert)\ **Post date:** [April 2, 2017, 12:08pm UTC](https://forum.arduino.cc/t/i-once-used-arduino-uno-as-a-hid-and-i-cant-turn-it-back-to-normal-arduino/449275/4 "2017-04-02T12:08:53Z")
Probably the same way you uploaded the keyboard firmware, just with the filename found at the folder I posted above, I believe the correct file is Arduino-COMBINED-dfu-usbserial-atmega16u2-Uno-Rev3.hex ---
**Author:** ![pineappleman](https://avatars.discourse-cdn.com/v4/letter/p/a5b964/32.png) [@pineappleman](https://forum.arduino.cc/u/pineappleman)\ **Post date:** [April 2, 2017, 12:14pm UTC](https://forum.arduino.cc/t/i-once-used-arduino-uno-as-a-hid-and-i-cant-turn-it-back-to-normal-arduino/449275/5 "2017-04-02T12:14:42Z")
Um... the thing is, that I can't use the computer I used to upload the keyboard firmware currently, so I can't find the proper folder path. Should I re-upload the dfu-programmer software and then erase it? ---
**Author:** ![pert](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/pert/32/217111_2.png) [@pert](https://forum.arduino.cc/u/pert)\ **Post date:** [April 2, 2017, 1:15pm UTC](https://forum.arduino.cc/t/i-once-used-arduino-uno-as-a-hid-and-i-cant-turn-it-back-to-normal-arduino/449275/6 "2017-04-02T13:15:48Z")
You don't upload the dfu-programmer software. You use the dfu-programmer software to upload the firmware file to the ATmega16U2. - Download the dfu-programmer software from [http://dfu-programmer.sourceforge.net/](http://dfu-programmer.sourceforge.net/) - Install dfu-programmer software following the instructions in the link you posted. - Follow the instructions at the "Revert USB Firmware" (USB 펌웨어 되돌리기) section of the link you posted. You may need to adjust the path to the file Arduino-COMBINED-dfu-usbserial-atmega16u2-Uno-Rev3.hex because that command assumes your Arduino IDE is installed at C:\arduino-1.0.5-r2\ and also newer IDE versions have a slightly different folder structure (avr folder)/ ---
**Author:** ![pineappleman](https://avatars.discourse-cdn.com/v4/letter/p/a5b964/32.png) [@pineappleman](https://forum.arduino.cc/u/pineappleman)\ **Post date:** [April 3, 2017, 10:47am UTC](https://forum.arduino.cc/t/i-once-used-arduino-uno-as-a-hid-and-i-cant-turn-it-back-to-normal-arduino/449275/7 "2017-04-03T10:47:58Z")
Thanks XD it works! ---
**Author:** ![system](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/system/32/1140315_2.png) [@system](https://forum.arduino.cc/u/system)\ **Post date:** [May 5, 2021, 4:14pm UTC](https://forum.arduino.cc/t/i-once-used-arduino-uno-as-a-hid-and-i-cant-turn-it-back-to-normal-arduino/449275/8 "2021-05-05T16:14:12Z")
Closed on May 5, 2021, 4:14pm UTC