The referenced script (Unknown) on this behaviour is missing! - how to fix?

[Kurt-Dekker]

SCRIPTS OR ASSETS ARE MISSING OR BLANK

ALWAYS move all Unity assets by using the Unity Editor. Any other way risks disconnecting the GUID in the meta file from the original file, and this will result in all connections to that asset being broken.

Some info about Missing script warnings, broken prefabs, GUIDs, renaming GUIDs, etc:

Problem with Git and missing scripts

If you delete a script and recreate it, Unity will produce a new .meta file, with a randomly chosen guid. The guid inside that metafile is what “connects” the script to the prefabs / scenes / assets. Here’s an example, with the guid fortuitously underlined with a red squiggle: [7024801--832060--Screen Shot 2021-04-10 at 9.13.40 AM.png] What you need to do is look in git history and find out what the original guid was for that file (the one you deleted when you deleted the script), then modif…

Scriptable Object data not read after loading editor.

The linkage between a scriptable object instance and its script is twofold. For one it is the GUID contained in the .meta file for the script, but the other requirement is the class and file naming requirement as you list above. For instance, this is my StartingShips scriptable object: (StartingShips.asset, NOT the meta file) %YAML 1.1 %TAG !u! tag:unity3d.com,2011: --- !u!114 &11400000 MonoBehaviour: m_ObjectHideFlags: 0 m_PrefabParentObject: {fileID: 0} m_PrefabInternal: {fileID: 0} …

Scriptable Object data not read after loading editor.

If you rename the class from within visual studio, the currently infuriating state of that function (for actually the past decade, going back to Monobehavior) is that it renames the .cs file but does NOT rename the .cs.meta file. Therefore, Unity throws out your original GUID, which you MAY have already used, and creates a new one when it creates the new .meta file. It is the single most Fisher-Price non-professional feature there is in Unity. It is probably responsible for more bugs and lost …

EVERYTHING in Unity is connected to the above GUID, which is stored ONLY in the metafile, and hence why the metafiles ALWAYS MUST be source-controlled.

When Renaming: It is super-easy to inadvertently change the GUID by renaming outside of Unity. Don’t do that. Instead:

• close Visual Studio (important!)
• rename the file(s) in Unity
• in Unity do Assets → Open C# Project to reopen Visual Studio
• now rename the actual classes, and MAKE SURE THE FILE NAMES DO NOT CHANGE!

If you are NOT using source control while you do this, renaming files is an EXTREMELY dangerous process. Use source control at all times so that you can trivially revert if you miss a critical step and damage your project.

For future reference:

If you post a code snippet, ALWAYS USE CODE TAGS:

How to use code tags: Using code tags properly

• Do not TALK about code without posting it.
• Do NOT post unformatted code.
  - Do NOT attach entire scripts to your post
• Do NOT retype code. Use copy/paste properly using code tags.
• Do NOT post screenshots of code.
• Do NOT post photographs of code.
• ONLY post the relevant code, and then refer to it in your discussion.