title: Failed to resolve: com.android.support:support-v13:26
body: <p>Everything has been working and compiling fine until I've added a TabLayout to an .xml layout. After I added it, the project just refused to compile and either all of my .xml files stopped showing anything and all of my library imports say &quot;cannot resolve symbol ...&quot;.</p>
  <p>I don't understand why all of my imports which had previously been compiling well now simply say:</p>
  <blockquote>
  <p>Failed to resolve: com.android.support:support-v13:26</p>
  <p>Failed to resolve: com.android.support:appcompat-v7:26</p>
  </blockquote>
  <p>and none of buttons provided (e.g. &quot;Install repository and sync project&quot;) are clickable.</p>
  <p>Please, have a look at the gradle file:</p>
  <pre><code>apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 26
      buildToolsVersion &quot;26.0.1&quot;
      defaultConfig {
          applicationId &quot;com.example.prett.myapplication&quot;
          minSdkVersion 22
          targetSdkVersion 26
          versionCode 1
          versionName &quot;1.0&quot;
          testInstrumentationRunner &quot;android.support.test.runner.AndroidJUnitRunner&quot;
      }
      buildTypes {
          release {
              minifyEnabled false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
          }
      }
      productFlavors {
      }
  }
  
  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'
      compile 'com.android.support:support-v13:26'
      compile 'com.android.support.constraint:constraint-layout:1.0.2'
      testCompile 'junit:junit:4.12'
      compile 'com.android.support:design:25.3.1'
  }
  </code></pre>
  <p>I've tried &quot;Invalidate caches/restart&quot;, but it didn't have any impact.</p>
  <p>P.S.</p>
  <p><code>compile 'com.android.support:design:25.3.1'</code></p>
  <p>says that</p>
  <blockquote>
  <p>This support library should not use a different version (25) than the compileSdkVersion (26)</p>
  </blockquote>
  <p>Could this also be causing the issue?</p>