What is this error message?

Before posting this question, I googled and didn’t find anything about it.

I got a this message from unity.

System.NullReferenceException: Object reference not set to an instance of an object
at System.Version.op_LessThan (System.Version v1, System.Version v2) [0x00000] in /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System/Version.cs:312
at SyntaxTree.VisualStudio.Unity.Bridge.VersionSpecificAssemblyGenerator…cctor () [0x00000] in :0
UnityEditor.EditorAssemblies:SetLoadedEditorAssemblies(Assembly)

I worked the project on Windows PC targeting Android

then opened it On Mac targeting IOS. And the unity said that error message.

That looks like Visual Studio things.

Any ideas?

That is one of the most common errors you’ll come across, and it means you are trying to do something with an object which is null.

I couldn’t tell you where or why this is happening with out seeing your code. Double clicking on the error in the console should take you to the offending line though.

Always test your objects for validity before accessing them!

I am encountering this same error. The majority of my project was built on Windows, but the project is for IOS. When I open the project on my Mac this shows up every time. Anyone have ideas on what might be causing this. It definitely seems Visual Studio specific.