Question Can't add script error

I closed the unity editor and do something else and restart it after 5 min and the "Can't add script" error occur for all of my code.

When I looked at the game object the error message is shown as below.

I checked that the script is indeed having the correct name and has no compile error.

I am not sure what is causing the problem and I tried "Reimport All" without any luck. Now I cannot even attach a newly created empty script to any game object.

I declined the auto-update that prompted half an hour ago would it be a possible reason?

 

are there any errors in the console?

 

If you have any compiler errors, you'll be unable to add scripts and you're see the Associated script can't be loaded message. I just noticed you said no compile errors(, but it can be a compile error in any script. Not just this one. Just when you load up the project, errors at that point can create this issue.

 

I checked that there is no compile error in the code, does it include other script?

 

That's what I said...if you have any compile errors in any script...

 

Thank you so much, the problem is resolved.