title: Firebase AB testing SDK error: abt.AbtException. Events collected in console, but 0 user included
body: <p>I'm setting up a remote config AB testing with self-defined events. 
  I can see my events in Dashboard/Events/DebugView as well as GCP Query. </p>
  
  <p>However, every experiment includes 0 user after several days and stops with an error.</p>
  
  <p>I checked the logcat as app running,  there was an firebase SDK (abt.AbtException )error alerted :</p>
  
  <pre class="lang-java prettyprint-override"><code>E/FirebaseRemoteConfig: Could not update ABT experiments.
     com.google.firebase.abt.AbtException: The Analytics SDK is not available. Please check that the Analytics SDK is included in your app dependencies.
         at com.google.firebase.abt.FirebaseABTesting.zzg(Unknown Source)
         at com.google.firebase.abt.FirebaseABTesting.replaceAllExperiments(Unknown Source)
         at com.google.firebase.remoteconfig.FirebaseRemoteConfig.zza(Unknown Source)
         at com.google.firebase.remoteconfig.zza.onSuccess(Unknown Source)
         at com.google.android.gms.tasks.zzn.run(Unknown Source)
         at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
         at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
         at java.lang.Thread.run(Thread.java:818)
  
  </code></pre>
  
  <p>My SDK versions are as follows:</p>
  
  <pre class="lang-java prettyprint-override"><code>compile 'com.google.firebase:firebase-core:16.0.8'
  compile 'com.google.firebase:firebase-perf:16.2.4'
  compile 'com.google.firebase:firebase-messaging:17.3.3'
  compile 'com.google.firebase:firebase-analytics:16.3.0'
  compile 'com.google.android.gms:play-services-measurement-sdk-api:16.3.0'
  </code></pre>
  
  <p>Also, firebase-config version is 16.4.0 , I'm sure it supports AB testing.</p>
  
  <p>I have referred to this Q&amp;A but none of them could solve my problem</p>
  
  <ul>
  <li><a href="https://stackoverflow.com/questions/50444991/ab-testing-config-applied-but-firebase-console-show-0-users">AB testing config applied but firebase console show 0 users</a></li>
  <li><a href="https://stackoverflow.com/questions/48915388/firebase-ab-test-has-0-users">Firebase AB Test has 0 users</a></li>
  <li><a href="https://stackoverflow.com/questions/49311141/firebase-remote-config-a-b-testing-shows-no-results-after-24-hours">Firebase Remote Config A/B testing shows no results after 24 hours</a></li>
  </ul>
  
  <p>Updating SDKs to the latest versions could be a lot risky. </p>
  
  <p>I wonder how I could solve this problem, many thanks!</p>