Adjusting blink software did not work

For testing, can you disable Bluetooth and try to upload?

I'm not sure what further wisdom is; one of the following might do the trick.

  1. In device manager, uninstall the device (Mega on COM4). Next disconnect and connect the board again.
  2. In device manager, with board disconnected, uninstall all hidden devices. Next connect the board again.
  3. In device manager, force a different COM port.

I did try (1); for (2) I only uninstalled the hidden Mega.

Thank you very very much for all the time you spent helping me.
It is now working. I think what did the trick was to uninstall the arduino com4 item, unplug and then re-plug the arduino board.
You are the best.
Jim

Great :+1:

Now some nagging. When posting code or error messages, in future please use code tags. If you click the <CODE/> button, it will create a ready to fill in block that looks like below

```
type or paste code here
```

Replace the text with your code or error message; make sure the three back ticks are on their own line. It makes it easier to read and copy and the forum software will display it correctly.

E.g. your upload output from post #17 will than look like

C:\Users\techn\AppData\Local\Arduino15\packages\arduino\tools\avrdude\6.3.0-arduino17/bin/avrdude -CC:\Users\techn\AppData\Local\Arduino15\packages\arduino\tools\avrdude\6.3.0-arduino17/etc/avrdude.conf -v -patmega2560 -cwiring -PCOM4 -b115200 -D -Uflash:w:C:\Users\techn\AppData\Local\Temp\arduino_build_373519/MyBlink.ino.hex:i

avrdude: Version 6.3-20190619

Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/

Copyright (c) 2007-2014 Joerg Wunsch

System wide configuration file is "C:\Users\techn\AppData\Local\Arduino15\packages\arduino\tools\avrdude\6.3.0-arduino17/etc/avrdude.conf"

Using Port : COM4

Using Programmer : wiring

Overriding Baud Rate : 115200

An error occurred while uploading the sketch

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.