Duplicated Classes Android

Unity Services
1

I’m trying to migrate from 2018 to 2020.
I do not have Unity Ads integrated but this error is throwing when building gradle

* What went wrong:
Execution failed for task ':launcher:checkReleaseDuplicateClasses'.
> 1 exception was raised by workers:
  java.lang.RuntimeException: Duplicate class com.unity3d.ads.BuildConfig found in modules jetified-UnityAds-runtime.jar (:UnityAds:) and jetified-unity-ads-3.4.2-runtime.jar (com.unity3d.ads:unity-ads:3.4.2)
  Duplicate class com.unity3d.ads.IUnityAdsListener found in modules jetified-UnityAds-runtime.jar (:UnityAds:) and jetified-unity-ads-3.4.2-runtime.jar (com.unity3d.ads:unity-ads:3.4.2)
  Duplicate class com.unity3d.ads.UnityAds found in modules jetified-UnityAds-runtime.jar (:UnityAds:) and jetified-unity-ads-3.4.2-runtime.jar (com.unity3d.ads:unity-ads:3.4.2)
  Duplicate class com.unity3d.ads.UnityAds$FinishState found in modules jetified-UnityAds-runtime.jar (:UnityAds:) and jetified-unity-ads-3.4.2-runtime.jar (com.unity3d.ads:unity-ads:3.4.2)
  Duplicate class com.unity3d.ads.UnityAds$PlacementState found in modules jetified-UnityAds-runtime.jar (:UnityAds:) and jetified-unity-ads-3.4.2-runtime.jar (com.unity3d.ads:unity-ads:3.4.2)
  Duplicate class com.unity3d.ads.UnityAds$UnityAdsError found in modules jetified-UnityAds-runtime.jar (:UnityAds:) and jetified-unity-ads-3.4.2-runtime.jar (com.unity3d.ads:unity-ads:3.4.2)
  Duplicate class com.unity3d.ads.mediation.IUnityAdsExtendedListener found in modules jetified-UnityAds-runtime.jar (:UnityAds:) and jetified-unity-ads-3.4.2-runtime.jar (com.unity3d.ads:unity-ads:3.4.2)
  Duplicate class com.unity3d.ads.metadata.InAppPurchaseMetaData found in modules jetified-UnityAds-runtime.jar (:UnityAds:) and jetified-unity-ads-3.4.2-runtime.jar (com.unity3d.ads:unity-ads:3.4.2)
2

I currently try to do exactly the same. - Same error. Did you have any solution?

3

I had such a problem.
In my case, Unity mediations and Unity Ads were installed into one project. But only one can be installed.
I uninstalled Unity Ads (Advertisement) and now all working properly.

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