unity (Android bild), i have problem "We can't assign a new GUID because the asset is in an immutable folder. The asset will be ignored."

According to this thread: https://github.com/firebase/quickstart-unity/issues/695

It looks like EDM4U is installed from both UPM and in Assets folder.

If you install any Firebase packages from UPM, EDM4U will be automatically installed through UPM as well, as a dependency. That is why we recommend to remove EDM4U from Assets folder BEFORE installing any Firebase SDK from UPM.

This may happen when you install any other packages including EDM4U or PlayServicesResolver in their .unitypackage, ex. Facebook, OneSignal. All you need is to remove those folders (Assets/ExternalDependencyManager and/or Assets/PlayServicesResolver) from Assets folder. Unfortunately EDM4U cannot resolve such installation conflict now but we are looking for some solution to make your life easier.

To resolve this, I recommend you to:

Remove Assets/ExternalDependencyManager and/or Assets/PlayServicesResolver folder

1. Uninstall all Firebase packages from UPM
2. Reinstall all needed Firebase packages from UPM (this guarantees assets ignored by Unity during previous installation is installed properly this time)

It looks like you have two of the same dll files conflicting with each other one here:

Assets/ExternalDependencyMAnager/Editor/Google.iOSResolver_v1.2.144.dll

and one in

Packages/com.google.external-dependency-manager/ExternalDependencyManager/Editor/Google.iOSResolver_v1.2.144.dll

Try deleting (cut and paste to a diff directory to do it safely) the Assets/ExternalDependencyManager/Editor/Google.iOSResolver_v1.2.144.dll

Unity is also telling you its in an immutable folder so it may not have permissions to access it itself

Installing Unity Ads To ensure the latest version of Unity Ads, download it through the Asset store, or through the Unity Package Manager in the Editor.

Important: You must choose either the Asset or the package. Installing both may lead to build errors. source

It helped me:

• Update Unity to 2019.4.15f
• Update Firebase to 6.16.1
• Update GooglePlayGamesPlugin-0.10.11
• Update GoogleMobileAds-v5.4.0 (optional)
• Remove Assets/ExternalDependencyManager and Assets/PlayServicesResolver folder

from unity editor 1.windows 2.package manager 3.In Project and Remove External dependencies folder or package.you can see package manager is open with In Project selected

In Unity 2020.3.11f1 LTS version: Just restart the Unity. The problem fixed for me.