Hello Henrik, your ESP32 is not in flashing mode. After pressing the upload button, (in some development boards) you need to hold down the BOOT/FLASH button.

Or you can try to add a capacitor to fix that issue permanently: https://randomnerdtutorials.com/solved-failed-to-connect-to-esp32-timed-out-waiting-for-packet-header/

Let me know if that works for you!

Hello Rui
Every time I transfer data from Arduino IDE to nodeMCU esp32s my port 4 disappears and I have installed CP210x USB to UART Bridge VCP drivers view photo

 
Arduino: 1.8.8 (Windows 10), Board: “NodeMCU-32S, 80MHz, 921600”
Sketch uses 650862 bytes (49%) of program storage space. Maximum is 1310720 bytes.
Global variables use 37040 bytes (11%) of dynamic memory, leaving 290640 bytes for local variables. Maximum is 327680 bytes.
esptool.py v2.6-beta1
Serial port COM4
Traceback (most recent call last):
File “esptool.py”, line 2865, in <module>
File “esptool.py”, line 2858, in _main
File “esptool.py”, line 2565, in main
File “esptool.py”, line 213, in __init__
File “site-packages\serial\__init__.py”, line 88, in serial_for_url
File “site-packages\serial\serialwin32.py”, line 62, in open
serial.serialutil.SerialException: could not open port ‘COM4’: WindowsError(2, ‘Den angivne fil blev ikke fundet.’)
Failed to execute script esptool
the selected serial port Failed to execute script esptool
does not exist or your board is not connected
This report would have more information with
“Show verbose output during compilation”
option enabled in File -> Preferences.

• But when you plug the ESP32 to your computer which COM port appears? Can you double-check again?
• If you remove the ESP32 board, does that COM port disappear? (before trying to upload any code)

Hello again
When I connect the ESP32, a com port does not appear and now I take it off again, nothing happens. The one for power only and one red light is on
When I connect my Arduino card, port com 3 comes up and I can transfer code to Arduino.
Thanks again

Hello Henrik, I apologize for taking so long to get back to you. If your ESP32 doesn’t appear it means one of these things:

• Serial drivers not installed (did you find your serial driver chip and installed the drivers?)
• Bad USB cable or USB cable without data wires (USB cables from powerbanks often don’t come with data wires)
• Which operating system are you using?

I think it can only be one of those two things… Can you tell me the exact serial chip that your ESP has?
Thanks!

Hello again
Thank you for your answers.
I have found the error, the USB cable that I used can only be used to let mobiles up and do not have data.
I replaced it with another one and now it works
See the picture

I hae a windows 10 laptop computer.

Thanks for letting me know and I’m glad you were able to make it work!

What does all the numbers say after the web name, for example
1: lillenet 2.4 GHZ (-56)
2: HomeBox_8c002.4 GHz (-69)
3
thanks