![Can't open device "\\.\COM4": Access is denied error when uploading a sketch from Arduino IDE | I learned it. I share it. Can't open device "\\.\COM4": Access is denied error when uploading a sketch from Arduino IDE | I learned it. I share it.](https://gyorgybalassy.files.wordpress.com/2020/10/arduino-port-selection.png)
Can't open device "\\.\COM4": Access is denied error when uploading a sketch from Arduino IDE | I learned it. I share it.
![Arduino Nano - "avrdude: ser_open():system can't open device "\\.\COM1": the system cannot find the file specified" - Stack Overflow Arduino Nano - "avrdude: ser_open():system can't open device "\\.\COM1": the system cannot find the file specified" - Stack Overflow](https://i.stack.imgur.com/PCjNG.png)
Arduino Nano - "avrdude: ser_open():system can't open device "\\.\COM1": the system cannot find the file specified" - Stack Overflow
![Can't open device "\\.\COM4": Access is denied error when uploading a sketch from Arduino IDE | I learned it. I share it. Can't open device "\\.\COM4": Access is denied error when uploading a sketch from Arduino IDE | I learned it. I share it.](https://gyorgybalassy.files.wordpress.com/2020/10/arduino-port-settings.png)
Can't open device "\\.\COM4": Access is denied error when uploading a sketch from Arduino IDE | I learned it. I share it.
![avrdude: ser_open(): can't open device "\\.\COM9": Access is denied. - Avrdude, stk500, Bootloader issues - Arduino Forum avrdude: ser_open(): can't open device "\\.\COM9": Access is denied. - Avrdude, stk500, Bootloader issues - Arduino Forum](https://europe1.discourse-cdn.com/arduino/original/4X/5/a/5/5a599607ba17e0f6fab970b65a3992b63195fda7.png)
avrdude: ser_open(): can't open device "\\.\COM9": Access is denied. - Avrdude, stk500, Bootloader issues - Arduino Forum
![avrdude: ser_open() : can't open device “\\. \COM4” : access denied | by Thusitha Wijerathne | Medium avrdude: ser_open() : can't open device “\\. \COM4” : access denied | by Thusitha Wijerathne | Medium](https://miro.medium.com/v2/resize:fit:1358/1*aTaQ38E9-MuR5mSK9TsO-Q.jpeg)
avrdude: ser_open() : can't open device “\\. \COM4” : access denied | by Thusitha Wijerathne | Medium
![avrdude: ser_open() : can't open device “\\. \COM4” : access denied | by Thusitha Wijerathne | Medium avrdude: ser_open() : can't open device “\\. \COM4” : access denied | by Thusitha Wijerathne | Medium](https://miro.medium.com/v2/resize:fit:1358/1*5cltkkk09Hyk1n6gsyz9Mg.jpeg)
avrdude: ser_open() : can't open device “\\. \COM4” : access denied | by Thusitha Wijerathne | Medium
Arduino IDE 1.6.8 - Can't open device error while uploading (No issue in 1.6.7) · Issue #4700 · arduino/Arduino · GitHub
![Flashing Wemos D1 Mini with ESPHome: Unexpected error: could not open port ' COM4': PermissionError(13, 'Access is denied.', None, 5) - Hardware - Home Assistant Community Flashing Wemos D1 Mini with ESPHome: Unexpected error: could not open port ' COM4': PermissionError(13, 'Access is denied.', None, 5) - Hardware - Home Assistant Community](https://community-assets.home-assistant.io/optimized/3X/e/5/e5179309676de3353239b6cbdd8a01d969181bb4_2_498x500.png)
Flashing Wemos D1 Mini with ESPHome: Unexpected error: could not open port ' COM4': PermissionError(13, 'Access is denied.', None, 5) - Hardware - Home Assistant Community
![Arduino Nano - "avrdude: ser_open():system can't open device "\\.\COM1": the system cannot find the file specified" - Stack Overflow Arduino Nano - "avrdude: ser_open():system can't open device "\\.\COM1": the system cannot find the file specified" - Stack Overflow](https://i.stack.imgur.com/cx8c7.png)
Arduino Nano - "avrdude: ser_open():system can't open device "\\.\COM1": the system cannot find the file specified" - Stack Overflow
![Can't open device "\\.\COM4": Access is denied error when uploading a sketch from Arduino IDE | I learned it. I share it. Can't open device "\\.\COM4": Access is denied error when uploading a sketch from Arduino IDE | I learned it. I share it.](https://gyorgybalassy.files.wordpress.com/2020/10/arduino-serial-port-in-device-manager.png)
Can't open device "\\.\COM4": Access is denied error when uploading a sketch from Arduino IDE | I learned it. I share it.
![Can't open device "\\.\COM4": Access is denied error when uploading a sketch from Arduino IDE | I learned it. I share it. Can't open device "\\.\COM4": Access is denied error when uploading a sketch from Arduino IDE | I learned it. I share it.](https://gyorgybalassy.files.wordpress.com/2020/10/arduino-port-properties.png)