Mono problem: "Your mono runtime and class libraries are out of sync"

Ggyrosp · Feb 8, 2018

Hello everbody :smile:. I started with godot 3.0 today and tried to write my first C#-Script. Unfortunately I get following error when I try to start the game:

Your mono runtime and class libraries are out of sync. The out of sync library is: C:\Program Files\Mono\lib\/mono/4.5/mscorlib.dll

When you update one from git you need to update, compile and install the other too. Do not report this as a bug unless you're sure you have updated correctly: you probably have a broken mono install. If you see other errors or faults after this message they are probably related and you need to fix your mono install first. ERROR: The build method threw an exception. System.MissingMethodException: Attempted to access a missing method. At: modules\mono\editor\godotsharp_builds.cpp:488

I did a fresh mono install today, too. Any help is really appreciated.

Best regards

WFGodot · Feb 28, 2018

Hi,

I had the same error with the most recent versions of mono. This version does not ask me these problems: https://download.mono-project.com/archive/5.4.1/windows-installer/mono-5.4.1.7-x64-0.msi On the download page (godotdevelopers.org) do not go wrong version but choose "Mono version (C # support)".

Greetings.