Missing Scripts in Prefabs/Objects

[vefak]

After first opening the project, the following bug is seen in the objects under the script section. This means that Unity did not load those scripts properly.

To fix this issue, you can try regenerating the meta files for your scripts. Here’s how to do it:

• Make a backup copy of your project before making any changes.
• Close Unity.
• Go to the project folder in your file explorer and delete the Library and Temp(if there is one) folders.
• Open Unity again and let it regenerate the Library and Temp folders. (this may take some time)
• Open your project and wait for Unity to finish importing all assets.

If this doesn’t work, there are a few other things you can try on below link
https://discussions.unity.com/t/missing-mono-script-when-it-really-exists/256830/2

You may get this error when you reopen the project:

• Click on Fix now, then re-compile again