Unity-Android _ CommandInvokationFailure: Unable to convert classes into dex format

Question

i'm using Windows 7, jdk 1.8.0 (64bit), jre 8 (64bit), Unity Pro 4.3.4f1 and Android SDK 22.6.1

All are updated softwares. All works fine but when i use StartApp sdk, this error comes. No extra plugin is used, only the SDK provided by the StartApp ad.

Error building Player: CommandInvokationFailure: Unable to convert classes into dex format. See the Console for details.
C:\Program Files\Java\jdk1.8.0\bin\java.exe -Xmx1024M -Dcom.android.sdkmanager.toolsdir="D:/android-sdks\tools" -Dfile.encoding=UTF8 -jar "C:/Program Files (x86)/Unity/Editor/Data/BuildTargetTools/AndroidPlayer\sdktools.jar" -

stderr[

UNEXPECTED TOP-LEVEL EXCEPTION:
java.lang.IllegalArgumentException: already added: Lcom/unity3d/player/a$1;
    at com.android.dx.dex.file.ClassDefsSection.add(ClassDefsSection.java:122)
    at com.android.dx.dex.file.DexFile.add(DexFile.java:161)
    at com.android.dx.command.dexer.Main.processClass(Main.java:685)
    at com.android.dx.command.dexer.Main.processFileBytes(Main.java:634)
    at com.android.dx.command.dexer.Main.access$600(Main.java:78)
    at com.android.dx.command.dexer.Main$1.processFileBytes(Main.java:572)
    at com.android.dx.cf.direct.ClassPathOpener.processArchive(ClassPathOpener.java:284)
    at com.android.dx.cf.direct.ClassPathOpener.processOne(ClassPathOpener.java:166)
    at com.android.dx.cf.direct.ClassPathOpener.processDirectory(ClassPathOpener.java:229)
    at com.android.dx.cf.direct.ClassPathOpener.processOne(ClassPathOpener.java:158)
    at com.android.dx.cf.direct.ClassPathOpener.process(ClassPathOpener.java:144)
    at com.android.dx.command.dexer.Main.processOne(Main.java:596)
    at com.android.dx.command.dexer.Main.processAllFiles(Main.java:498)
    at com.android.dx.command.dexer.Main.runMonoDex(Main.java:264)
    at com.android.dx.command.dexer.Main.run(Main.java:230)
    at com.android.dx.command.dexer.Main.main(Main.java:199)
    at com.android.dx.command.Main.main(Main.java:103)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at SDKMain.main(SDKMain.java:129)
1 error; aborting
]

I already tried JAVA_OPT and JAVA_HOME solutions. But still couldn't solved

Answer 1

I ran into this using IntelliJ 13.1.4, JDK 1.6 but I would guess that this is caused by the same thing on any other IDE -> classes.jar is referenced/included more than once.

Check and make sure that the classes.jar you added to the project (from Unity\Editor\Data\PlaybackEngines\androidplayer\bin\classes.jar) isn't referenced/included more than once. If you go into File->Project Structure: There should only be one "classes" under libraries. There should be NO reference to classes under Artifacts (Artifacts is used to create the plugin .jar file.)

Check out this related answer -> https://stackoverflow.com/a/8437996/3464367