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Runtime Exception Debugging

You will often find yourself with programs that can only be debugged in-game. In order to catch these errors and make them easier to understand, U# includes a runtime exception watcher that will look for exceptions from VRChat's output log. The watcher will then output the script and line that threw that exception to your editor's log.

Setup instructions

Editor setup

  1. In your editor open the project settings menu

Project Settings

  1. Enable Listen for client exceptions in the Udon Sharp settings

Listen for Client Exceptions

VRChat client setup

  1. Right-click on VRChat in your Steam library and click Properties...

Steam VRChat Properties

  1. Click Set Launch Options...

Set Launch Options

  1. Add the launch argument --enable-udon-debug-logging to the launch options and click OK

Steam Launch Args


Now once you have the client and editor setup, you just need to start your game and load into the world. Any errors that are thrown in your world will be output to your editor's console. This is an example of what the error will look like, you probably won't be getting the same error and it won't be in the same code file.

Error in Console