Got error on authenticate: Could not register one or more required Java classes.

[Mokalipilou]

Hi, After two days of tests and lot of google search, trying to fix an authentification failure, i ended with this logcat error. This occurs on a previously working (and published) project, updated to Unity 2017.3.1f1 and to GPG 0.9.50 :

03-23 21:01:10.465: E/GamesNativeSDK(11435): Could not register one or more required Java classes. 03-23 21:01:10.475: E/Unity(11435): InvalidOperationException: There was an error creating a GameServices object. Check for log errors from GamesNativeSDK 03-23 21:01:10.475: E/Unity(11435): at GooglePlayGames.Native.PInvoke.GameServicesBuilder.Build (GooglePlayGames.Native.PInvoke.PlatformConfiguration configRef) [0x00000] in :0 03-23 21:01:10.475: E/Unity(11435): at GooglePlayGames.Native.NativeClient.InitializeGameServices () [0x00000] in :0 03-23 21:01:10.475: E/Unity(11435): at GooglePlayGames.Native.NativeClient.Authenticate (System.Action2 callback, Boolean silent) [0x00000] in <filename unknown>:0 03-23 21:01:10.475: E/Unity(11435): at GooglePlayGames.PlayGamesPlatform.Authenticate (System.Action2 callback, Boolean silent) [0x00000] in :0 03-23 21:01:10.475: E/Unity(11435): at GooglePlayGames.PlayGamesPlatform.Authenticate (System.Action1 callback, Boolean silent) [0x00000] in <filename unknown>:0 03-23 21:01:10.475: E/Unity(11435): at GooglePlayGames.PlayGamesPlatform.Authenticate (System.Action1 callback) [0x00000] in :0 03-23 21:01:10.475: E/Unity(11435): at GooglePlayGames.PlayGamesLocalUser.Authenticate (System.Action`1 callback) [0x00000] in :0 03-23 21:01:10.475: E/Unity(11435): at GameManager [...]

• A freshly created minimal sample GPG project, set with the same GPG game data, works.
• JAVA_HOME path is set, GPG resources are set, and "setup" button has been clicked again.
• I deleted GPG and AdMobs file and i reinstalled only the former.
• Build mode is set to "Gradle". Build "Internal" mode, as i always used before, won't even build anymore (the building process complains of the failure of a jar file move from and to the temp directory).
• I removed the following entries in SDK Manager : Android Support Repository, Android Support Library, Google Play services, Google Repository. This in order to reinstall them, but "Android Support Library" doesn't appear anymore in the Extras section, hence can't be installed anymore. (but that doesn't prevent the Sample project to work). I don't see it in Android Studio SDK Tools either. Is that package normal?
• The Plugins/Android mode has 24 files (like "com.android.support.support-annotations-25.2.0") but i copied them manually from the working minimal sample project because when i use Asset/Play Service Resolver/Android Resolver/Fore Resolve, it create those files (see image) but when i click ok, all those files disappears from the Unity editor! If i don't add those files manually, i get this logcat error instead when the game tries to connect:

03-23 20:35:58.615: E/Unity(30105): DllNotFoundException: gpg 03-23 20:35:58.615: E/Unity(30105): at (wrapper managed-to-native) GooglePlayGames.Native.Cwrapper.Builder:GameServices_Builder_Construct () 03-23 20:35:58.615: E/Unity(30105): at GooglePlayGames.Native.PInvoke.GameServicesBuilder.Create () [0x00000] in :0 03-23 20:35:58.615: E/Unity(30105): at GooglePlayGames.Native.NativeClient.InitializeGameServices () [0x00000] in :0 03-23 20:35:58.615: E/Unity(30105): at GooglePlayGames.Native.NativeClient.Authenticate (System.Action2 callback, Boolean silent) [0x00000] in <filename unknown>:0 03-23 20:35:58.615: E/Unity(30105): at GooglePlayGames.PlayGamesPlatform.Authenticate (System.Action2 callback, Boolean silent) [0x00000] in :0 03-23 20:35:58.615: E/Unity(30105): at GooglePlayGames.PlayGamesPlatform.Authenticate (System.Action1 callback, Boolean silent) [0x00000] in <filename unknown>:0 03-23 20:35:58.615: E/Unity(30105): at GooglePlayGames.PlayGamesPlatform.Authenticate (System.Action1 callback) [0x00000] in :0 03-23 20:35:58.615: E/Unity(30105): at GooglePlayGames.PlayGamesLocalUser.Authenticate (System.Action`1 callback) [0x00000] in :0 03-23 20:35:58.615: E/Unity(30105): at GameManager.GooglePlayGamesActivate (Boolean on) [0x000

I'm running out of clue right know. Any help would be welcome.

[Mokalipilou]

After two more days, i found the source of the error "Could not register one or more required Java classes.": the Play Service Resolver, run in the Sample project, failed to show an error when it fails to correctly create the assets in the plugin/android directory due to the complete path to filenames to be too long. This also didn't prevent the gradle to build the project. Given the length of the path of these dependencies, it is easy to exceeds the length limit on Windows if you put your projects in a usual directory like C:\Users\%USERNAME%\Documents\Unity\project_name

The current solution for me has been to move my projects directory to the root directory.

This still doesn't explain why the Play Service Resolver fails totally on my main project, despite saying it succeed (i'm then using files generated in the sample project).