IDE hangs on startup: "YAMLException: end of the stream or a document separator is expected"

[ptillisch]

Hi @wcho. The problem is caused by corruption in the configuration file located at the following path on your hard drive:

c:\Users\ethanho\.arduinoIDE\arduino-cli.yaml

I would guess you manually edited this file in an attempt to increase the download timeout, as described here:

ESP32 Devkit1 library not downloading

Hi @faiiz. The installation of the "esp32" boards platform failed due to timeout occurred during the download. The duration of the timeout that causes Arduino IDE to cancel a download is configurable. You should be able to work around this problem by configuring a higher timeout value. I'll provide instructions you can follow to do that: Select File > Quit from the Arduino IDE menus if it is running. All Arduino IDE windows will close. Open the file at the following path in any text editor: …

Is that correct?