[FIXED] Gradle Error:Execution failed for task ':app:processDebugGoogleServices'

Issue

I am following this link to integrate Google sign-in in my android app.https://developers.google.com/identity/sign-in/android/start-integrating As given in last step on the above given page we have to include dependency

 compile 'com.google.android.gms:play-services-auth:8.3.0' 

in app-level build.gradle file but doing so and building project an error comes saying

Error:Execution failed for task ':app:processDebugGoogleServices'.
> Please fix the version conflict.

build.gradle(Module:app)

apply plugin: 'com.android.application'
apply plugin: 'com.google.gms.google-services'


android {
    compileSdkVersion 23
    buildToolsVersion "23.0.2"

    defaultConfig {
        applicationId "com.brainbreaker.socialbuttons"
        minSdkVersion 16
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.0.1'
    compile 'com.android.support:design:23.0.1'
    compile 'com.google.android.gms:play-services-auth:8.3.0'
}

In the build.gradle file the compile dependency line compile 'com.google.android.gms:play-services-auth:8.3.0' shows error

All com.google.android.gms libraries must use the exact same version specification (mixing versions can lead to runtime crashes). Found versions 8.3.0, 8.1.0. Examples include com.google.android.gms:play-services-base:8.3.0 and com.google.android.gms:play-services-measurement:8.1.0 There are some combinations of libraries, or tools and libraries, that are incompatible, or can lead to bugs. One such incompatibility is compiling with a version of the Android support libraries that is not the latest version (or in particular, a version lower than your targetSdkVersion.)

Here are the messages of gradle build.

Information:Gradle tasks [clean, :app:generateDebugSources, :app:generateDebugAndroidTestSources, :app:compileDebugSources, :app:compileDebugAndroidTestSources, :social_buttons:generateDebugSources, :social_buttons:generateDebugAndroidTestSources, :social_buttons:compileDebugSources, :social_buttons:compileDebugAndroidTestSources]
:clean UP-TO-DATE
:app:clean
:social_buttons:clean
:app:preBuild UP-TO-DATE
:app:preDebugBuild UP-TO-DATE
:app:checkDebugManifest
:app:preReleaseBuild UP-TO-DATE
:app:prepareComAndroidSupportAppcompatV72301Library
:app:prepareComAndroidSupportDesign2301Library
:app:prepareComAndroidSupportSupportV42301Library
:app:prepareComGoogleAndroidGmsPlayServicesAds810Library
:app:prepareComGoogleAndroidGmsPlayServicesAnalytics810Library
:app:prepareComGoogleAndroidGmsPlayServicesAppindexing810Library
:app:prepareComGoogleAndroidGmsPlayServicesAuth830Library
:app:prepareComGoogleAndroidGmsPlayServicesBase830Library
:app:prepareComGoogleAndroidGmsPlayServicesBasement830Library
:app:prepareComGoogleAndroidGmsPlayServicesMeasurement810Library
:app:prepareDebugDependencies
:app:compileDebugAidl
:app:compileDebugRenderscript
:app:generateDebugBuildConfig
:app:generateDebugAssets UP-TO-DATE
:app:mergeDebugAssets
:app:generateDebugResValues UP-TO-DATE
:app:processDebugGoogleServices
Found com.google.android.gms:play-services-auth:8.3.0, but version 8.1.0 is needed
Found com.google.android.gms:play-services-auth:8.3.0, but version 8.1.0 is needed
Found com.google.android.gms:play-services-auth:8.3.0, but version 8.1.0 is needed
Found com.google.android.gms:play-services-auth:8.3.0, but version 8.1.0 is needed
Found com.google.android.gms:play-services-auth:8.3.0, but version 8.1.0 is needed
:app:processDebugGoogleServices FAILED
Error:Execution failed for task ':app:processDebugGoogleServices'.
> Please fix the version conflict.
Information:BUILD FAILED
Information:Total time: 3.49 secs
Information:1 error
Information:0 warnings
Information:See complete output in console

I am not able to see any way out for this version conflict. Any help is appreciated.

Solution

I'v got a same issue. but Now I'm fixed.

You should delete a line apply plugin: 'com.google.gms.google-services'

because "com.android.application" package already has same package.

Answered By - seyeon
Answer Checked By - Marie Seifert (JavaFixing Admin)