Gradle build tool cannot find play-services-tasks.aar? Why?

Question

Today suddenly, I got an error when I tried to run my app in Android studio.

It is:

Error: Could not find play-services-tasks.aar (com.google.android.gms:play-services-tasks:15.0.1).
Searched in the following locations:
    https://jcenter.bintray.com/com/google/android/gms/play-services-tasks/15.0.1/play-services-tasks-15.0.1.aar

I didn't change anything in the gradle file but it appeared suddenly. My previous build executed successfully some minutes ago.

Why it can't find play-services-tasks.aar which is the part of com.google.android.gms:play-services-tasks:15.0.1

Steps taken:

I checked whether I included all repositories in the gradle files and all are correct so far.

Why does this error occur all of a sudden?

I also copied this link https://jcenter.bintray.com/com/google/android/gms/play-services-tasks/15.0.1/play-services-tasks-15.0.1.aar into the browser but it's working fine, that is, I got "File Download" dialog.

---

My Gradle Files

• App level

  apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 26
      buildToolsVersion "26.0.2"
      defaultConfig {
          applicationId "mekanic24assistantapplication.heba.mekanic24.com.mekanic24assistantapplication"
          minSdkVersion 14
          targetSdkVersion 26
          versionCode 13
          versionName "2.1"
          testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
          multiDexEnabled true
      }
      buildTypes {
          release {
              minifyEnabled false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
          }
      }
  
  
      dexOptions {
          incremental true
          javaMaxHeapSize "4g"
      }
  
  //    err Android Gradle Duplicate files copied in APK META-INF/license.txt
  
      configurations.all {
  
          resolutionStrategy {
              force 'com.android.support:support-v4:26+'
              force 'com.android.support:support-annotations:26+'
  
  
          }
  
      }
  
  
      packagingOptions {
          exclude 'META-INF/DEPENDENCIES.txt'
          exclude 'META-INF/LICENSE.txt'
          exclude 'META-INF/NOTICE.txt'
          exclude 'META-INF/NOTICE'
          exclude 'META-INF/LICENSE'
          exclude 'META-INF/DEPENDENCIES'
          exclude 'META-INF/notice.txt'
          exclude 'META-INF/license.txt'
          exclude 'META-INF/dependencies.txt'
          exclude 'META-INF/LGPL2.1'
      }
  
  }
  
  dependencies {
      compile fileTree(include: ['*.jar'], dir: 'libs')
      androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
          exclude group: 'com.android.support', module: 'support-annotations'
      })
      //   compile 'com.android.support:appcompat-v7:26.3.1'
      compile 'com.android.support:appcompat-v7:26+'
      compile 'com.android.support:design:26+'
      compile 'com.android.support:recyclerview-v7:26+'
      compile 'com.android.support:cardview-v7:26+'
      compile 'com.android.support.constraint:constraint-layout:1.0.2'
      androidTestCompile 'com.android.support:support-annotations:26+'
      testCompile 'junit:junit:4.12'
      //   compile 'com.android.support:appcompat-v7:26.3.1'
      compile 'com.github.markushi:circlebutton:1.1'
      //  compile 'com.android.support:design:26.3.1'
      compile 'com.android.volley:volley:1.0.0'
      compile 'com.google.android.gms:play-services-base:15.0.1'
      compile 'com.android.support:multidex:1.0.1'
      compile 'com.firebase:firebase-client-android:2.5.2'
      compile 'com.google.firebase:firebase-core:15.0.2'
      compile 'com.google.firebase:firebase-messaging:15.0.2'
      compile 'com.google.firebase:firebase-database:15.0.0'
      compile 'com.wang.avi:library:2.1.3'
      compile 'de.hdodenhof:circleimageview:2.2.0'
      compile 'android.lib.recaptcha:reCAPTCHA:2.0.0'
      compile 'com.google.android.gms:play-services-safetynet:15.0.1'
      compile 'com.google.android.gms:play-services-maps:15.0.1'
      compile 'com.google.android.gms:play-services-places:15.0.1'
      compile 'com.google.android.gms:play-services-location:15.0.1'
  
      compile 'com.squareup.picasso:picasso:2.5.2'
      testCompile 'junit:junit:4.12'
      compile 'com.anjlab.android.iab.v3:library:1.0.38'
      compile files('libs/mail.jar')
      compile files('libs/additionnal.jar')
      compile files('libs/activation.jar')
      compile 'com.jakewharton:butterknife:8.8.1'
      annotationProcessor 'com.jakewharton:butterknife-compiler:8.8.1'
      compile 'com.yarolegovich:lovely-dialog:1.1.0'
      compile 'com.mobsandgeeks:android-saripaar:2.0.3'
      compile 'com.github.stfalcon:smsverifycatcher:0.3.1'
      compile 'ch.acra:acra:4.9.0'
      //TODO:  Apache 2.0 license https://github.com/ACRA/acra
      compile 'com.google.android.gms:play-services-ads:15.0.1'
      compile 'com.github.luongvo:GmailBackground:2.0.2'
  
  }
  apply plugin: 'com.google.gms.google-services'
  

• Project Level
  
  

  buildscript {
  repositories {
      jcenter()
      maven { url 'https://maven.google.com' }
      maven {
          url "https://dl.bintray.com/android/android-tools"
      }
  
      maven { url "https://jitpack.io" }
      google()
  
  }
  dependencies {
      classpath 'com.android.tools.build:gradle:2.3.2'
  
      classpath 'com.google.gms:google-services:3.2.0'
  }
  }
  
  allprojects {
  repositories {
      jcenter()
      maven { url 'https://maven.google.com' }
      maven {
          url "https://dl.bintray.com/android/android-tools"
      }
  
      maven { url "https://jitpack.io" }
      google()
  
  }
  }
  
  task clean(type: Delete) {
  delete rootProject.buildDir
  }
  

Answer 1

After doing the following changes the error disappeared:

1. Removed maven { url 'https://maven.google.com' } from repositories in app build.gradle.
2. Added maven { url 'https://maven.google.com' } as first entry in allprojects/repositories in top level build.gradle
3. Changed all play-services and firebase dependencies to the latest versions
4. Changed version of google-services plugin to classpath 'com.google.gms:google-services:4.0.1'