# Arduino Nano ESP32s are often becoming unprogrammable **URL:** \ **Category:** Uploading\ **Created:** [July 22, 2025, 7:16pm UTC](https://forum.arduino.cc/t/arduino-nano-esp32s-are-often-becoming-unprogrammable/1397307 "2025-07-22T19:16:07Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![luckybuddy0987](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/luckybuddy0987/32/1138823_2.png) [@luckybuddy0987](https://forum.arduino.cc/u/luckybuddy0987)\ **Post date:** [July 22, 2025, 7:16pm UTC](https://forum.arduino.cc/t/arduino-nano-esp32s-are-often-becoming-unprogrammable/1397307/1 "2025-07-22T19:16:07Z")
I was working on a custom BT Keyboard with an Arduino Nano ESP32, and everything was working fine. I wanted to see if I could improve the sketch so that it would use less energy, which didn't work. Now I am unable even to upload an empty sketch to the Arduino. This issue is getting very frustrating. As I currently have 6 Nanos that I was programming with **3 completely different scripts** that are unable to be programmed, despite trying everything I can find on the internet. This is the error I get: ```arduino "C:\Users\UserName\AppData\Local\Arduino15\packages\arduino\tools\dfu-util\0.11.0-arduino5/dfu-util" --device 0x2341:0x0070 -D "C:\Users\UserName\AppData\Local\arduino\sketches\B6AD3EDCF267622E93B4AC5955914B4C/BT_low_power.ino.bin" -Q Failed to retrieve language identifiers Failed to retrieve language identifiers error get_status: LIBUSB_ERROR_PIPE dfu-util 0.11-arduino4 Copyright 2005-2009 Weston Schmidt, Harald Welte and OpenMoko Inc. Copyright 2010-2021 Tormod Volden and Stefan Schmidt This program is Free Software and has ABSOLUTELY NO WARRANTY Please report bugs to http://sourceforge.net/p/dfu-util/tickets/ Opening DFU capable USB device... Device ID 2341:0070 Device DFU version 0101 Claiming USB DFU Interface... Setting Alternate Interface #0 ... Determining device status... Failed uploading: uploading error: exit status 74 ``` ### I have tried: 1. Clearing all items (_even hidden_) in Device Manager 2. Resetting the Arduino in every way I could find 3. Switching cables 4. Unplugging all external devices and restarting my computer 5. Using a completely different computer and uploading a blink sketch Here are all the forum posts that I have gone through so far: > [@Problem with COM ports, please help me understand](https://forum.arduino.cc/t/problem-with-com-ports-please-help-me-understand/1182299): > > Hi everyone. Sorry if this is a noob question, but I'm stumped and really need some guidance. I just got an Arduino UNO R4 wifi and I'm trying to use it for the first time. The thing is, no matter what USB port I connect my Arduino to, it always shows like COM6. I cannot select any other port on the IDE (version 2.2.1). Is this supposed to work like this? If my Arduino is not on what I'm assuming is the real COM6, I get this error, get this error, even though the IDE says my Arduino is at COM6: … > [@Problem with COM ports, please help me understand](https://forum.arduino.cc/t/problem-with-com-ports-please-help-me-understand/1182299): > > Hi everyone. Sorry if this is a noob question, but I'm stumped and really need some guidance. I just got an Arduino UNO R4 wifi and I'm trying to use it for the first time. The thing is, no matter what USB port I connect my Arduino to, it always shows like COM6. I cannot select any other port on the IDE (version 2.2.1). Is this supposed to work like this? If my Arduino is not on what I'm assuming is the real COM6, I get this error, get this error, even though the IDE says my Arduino is at COM6: … > [@HOWTO: Reset your Arduino when serial port is overflow or upload hang](https://forum.arduino.cc/t/howto-reset-your-arduino-when-serial-port-is-overflow-or-upload-hang/272195): > > New to Arduino, I was playing with loop and serial output. Didn't take long that I overflow the serial buffer and Arduino IDE was not able to upload any code and hang there. I try multiple RESET, update driver,etc but none work and I was also receiving PORT already open/used. After scratching my head about this problem and search on the internet, I found a very simple SOLUTION that I would like to share that work anytime and you don't need a programmer or other tools. Unplug your USB Cable Go… [https://support.arduino.cc/hc/en-us/articles/11011849739804-dfu-util-errors-when-uploading-exit-status-74](https://support.arduino.cc/hc/en-us/articles/11011849739804-dfu-util-errors-when-uploading-exit-status-74) > [@Failed uploading: uploading error: exit status 74](https://forum.arduino.cc/t/failed-uploading-uploading-error-exit-status-74/1037954): > > Hey all, I am working with an Arduino Portenta Machine Control and looking to control a motor with it. To start learning this new board I looked through the examples and uploaded one. This all worked fine, however now it does not want to upload a sketch anymore. I am using the new 2.0.0 Arduino IDE Trying to upload the Arduino\_MachineControl.h Digital\_Input.ino sketch And I get the following error. Sketch uses 164024 bytes (20%) of program storage space. Maximum is 786432 bytes. Global var… [https://support.arduino.cc/hc/en-us/articles/4403365313810-If-your-sketch-doesn-t-upload](https://support.arduino.cc/hc/en-us/articles/4403365313810-If-your-sketch-doesn-t-upload) ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [July 22, 2025, 7:59pm UTC](https://forum.arduino.cc/t/arduino-nano-esp32s-are-often-becoming-unprogrammable/1397307/3 "2025-07-22T19:59:15Z")
What you have not done is consult the docs for this special board. An Arduino NANO ESP32 is part Arduino and part ESP32. I am no expert, but your error logs look like you are in DFU mode instead of normal. Somewhere in the docs are instructions for how to do a reset. Sorry, my heart is acting up today, so that is the best I can do. ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [July 22, 2025, 8:05pm UTC](https://forum.arduino.cc/t/arduino-nano-esp32s-are-often-becoming-unprogrammable/1397307/4 "2025-07-22T20:05:22Z")
I think this is your problem solved. [https://forum.arduino.cc/t/arduino-nano-esp32-s3-no-dfu-capable-usb-device-available-solved/1251053](https://forum.arduino.cc/t/arduino-nano-esp32-s3-no-dfu-capable-usb-device-available-solved/1251053) ---
**Author:** ![luckybuddy0987](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/luckybuddy0987/32/1138823_2.png) [@luckybuddy0987](https://forum.arduino.cc/u/luckybuddy0987)\ **Post date:** [July 24, 2025, 3:54pm UTC](https://forum.arduino.cc/t/arduino-nano-esp32s-are-often-becoming-unprogrammable/1397307/5 "2025-07-24T15:54:38Z")
Yes this was the solution: [https://support.arduino.cc/hc/en-us/articles/9810414060188-Reset-the-Arduino-bootloader-on-the-Nano-ESP32](https://support.arduino.cc/hc/en-us/articles/9810414060188-Reset-the-Arduino-bootloader-on-the-Nano-ESP32) ---
**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:** [January 20, 2026, 3:54pm UTC](https://forum.arduino.cc/t/arduino-nano-esp32s-are-often-becoming-unprogrammable/1397307/6 "2026-01-20T15:54:51Z")
Closed on January 20, 2026, 3:54pm UTC This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.