Unity - CommandInvokationFailure: Gradle build failed

Question

All of a sudden, Gradle fails to build and throws the following error:

CommandInvokationFailure: Gradle build failed. D:\Unity\Editor\Data\PlaybackEngines\AndroidPlayer/Tools\OpenJDK\Windows\bin\java.exe -classpath "D:\Unity\Editor\Data\PlaybackEngines\AndroidPlayer\Tools\gradle\lib\gradle-launcher-4.6.jar" org.gradle.launcher.GradleMain "-Dorg.gradle.jvmargs=-Xmx4096m" "assembleRelease"

stderr[ D8: Program type already present: com.unity3d.ads.BuildConfig

FAILURE: Build failed with an exception.

• What went wrong: Execution failed for task ':transformDexArchiveWithExternalLibsDexMergerForRelease'.

  com.android.builder.dexing.DexArchiveMergerException: Error while merging dex archives: D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\0.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\1.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\2.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\3.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\4.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\5.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\6.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\7.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\8.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\9.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\10.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\11.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\12.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\13.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\14.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\15.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\16.jar, D:\Unity Projects\VegOrNonVeg\Temp\gradleOut\build\intermediates\transforms\dexBuilder\release\17.jar Learn how to resolve the issue at https://developer.android.com/studio/build/dependencies#duplicate_classes. Program type already present: com.unity3d.ads.BuildConfig

• Try: Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

I've tried uninstalling the existing SDK and reinstalled SDK for Oreo

I'm also getting the following error: UnityAdsEditor: Initialize(3113808, False); UnityEditor.Advertisements.UnityAdsEditor:EditorOnLoad()

The project had no issues before. No new update or any code changes.

Answer 1

Issue Resolved:

The existing package for Unity Ads was causing this problem.

Go to Package Manager and Remove/Update the Advertisement package (Mine was 2.0.8, updated it to 3.0.3).

Go to Edit > Project Settings > Player and select .NET 4.x Equivalent for the Scripting Runtime Version under Configuration.

If possible choose Minimum API Level as 19 or above.

Make sure to delete the existing Unity Ads folder if present in the Assets Folder of the Project window.