Can't add script component because the script class cannot be found?

Question

Yesterday I updated unity from unity5 to 2018.2.2f1. Unity scripts are not loading after Update 2018.2.2f1.

Once I try to play the Scene the scripts are not loaded and I can't add the script again it gives this error:

Can't add script component 'CubeScript' because the script class cannot be found. Make sure that there are no compile errors and that the file name and class name match.

Answer 1

If you still have the old copy of the project, upgrade the Unity project to Unity 2017 first then to 2018.2.2f1 .

Here are the few possible reasons you may get this error(Ordered from very likely)

1 .Script name does not match class name.

If script name is called MyClass , the class name must be MyClass . This is also case-sensitive. Double check to make sure that this is not the issue. To make sure that's not the issue, copy the class name and paste it as the script name to make sure that this is not the issue.

Note that if you have have multiple classes in one script, the class name that should match with the script name is the class that derives from MonoBehaviour .

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2 .There is an error in your script. Since this is an upgrade, there is a chance you're using an API that is now deprecated and removed. Open your script with Visual Studio and see if there is an error there then fix it. There is usually a red line under a code that indicates there is an error.

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3 .Bad import with the Unity importer and its automatic upgrade script.

Things to try:

A .The first thing to do is restart the Unity Editor.

B .Right click on the Project Tab then click "Reimport All"

C .If there is still issue, the only left is deleting the problematic script and creating a new one. There is an easier way to do this if the script is attached to many GameObjects in your scene.

A .Open the script, copy its content into notepad.

B .From the Editor and on the Project tab right click on the script "CubeScript", select "Find References In Scene" .

C .Unity will now only show all the GameObjects that has this script attached to them. Delete the old script. Create a new one then copy the content from the notepad to this new script. Now, you can just drag the new script to all the filtered GameObject in the scene. Do this for every script effected. This is a manual work but should fix your issues when completed.

Answer 2

Posting here for historic purposes and if someone from Google ends up here, I strictly had the same problem (I'm on Windows 10) and here's how I fixed it :

• If you click on the Console, you should see a blank error. Don't worry, it's a Editor bug, and you can see the Editor Log by selecting the console's window dropdown and selecting Open Editor Log .

For me, the problem was that "Tools\Roslyn\csc" could not be found, something that Unity uses to compile C# files.

• I opened C:\Program Files\Unity\Hub\Editor\2019.2.14f1\Editor\Data\Tools\RoslynScripts\unity_csc.bat and I added ".exe" to the line "%APPLICATION_CONTENTS%\Tools\Roslyn\csc" /shared %*

(This line should now be : "%APPLICATION_CONTENTS%\Tools\Roslyn\csc.exe" /shared %* )

Now it works perfectly.

Answer 3

Here, is some reason why that's heaping.

1 . Your Script Name And your class name isn't same.

2 . May be there is an error in your script.

Here, is the few way to resolve it.

1 . Make a same name of script and class in to this script.

2 . find there is the error? and try to resolve it.

Answer 4

我对 Unity 和游戏开发完全陌生，但我发现通过输入错误的名称使错误为真，然后输入正确的名称似乎会“欺骗”Unity 修复其错误。

Answer 5

I had the same error show up but for different reasons (in case someone ends up here from google).

I was a beginner and named my file with a space in it. I got the same error after that. Make sure to NOT include spaces in your C# script.

Answer 6

One more thing which might help apart from other answers

• Make the class which inherits from the MonoBehaviour the first class in the file. It fixed this issue for me.

Answer 7

Checking the console bugs and fix them is a good way to solve the problems "Can't add script component because the script class cannot be found?", although the bug seems to be irrelevant. This works for me when I fix a bug in the other script.

Answer 8

对我来说，我发现这是一个我没有使用的脚本，它链接到我删除的播放器和其他脚本。

Answer 9

For me, the problem was that there was an error in another script.

Once I fixed the error, I could FINALLY attach my other scripts onto my gameobjects.

Answer 10

I just had this issue where I had a perfect script, no errors, and the same name as it should be but no matter what it wouldn't let me add it to a gameObject. There was another script that was completely unrelated but it had an error in that and somehow that prevented me from adding my good new script.

Answer 11

Like some folks already posted here - the issue might be of a different code. I was trying to add a script that was referenced by another one which had errors - it doesn't tell you that is the reason, although visual studio kinda suggests it by showing you the errors in the open script.

Just delete the bigger (errored) script and start adding to the unity project from the basic ones.

Answer 12

I had this issue where I had a good script, no errors, good name, restarting unity, following a tutorial exactly but still had this issue.

The way I fixed this is just deleting this buggy script file and creating it again. It fixed my problem perfectly! Now I could add the script to my game object with no such errors!

Hope this helps you! Cheers!

Answer 13

No one seems to have the answer for this issue that started appearing more than 2 years ago. It's beyond frustrating. If you create a script from withing Unity, the editor should be able to recognize the damn thing! I'm going back to Unreal Engine. The support for Unity sucks!!!!!