title: Error:Execution failed for task ':app:mergeDebugResources'. > -1
body: <p>Whenever I run, make, or clean project,</p>
  
  <pre><code>Error:Execution failed for task ':app:mergeDebugResources'.&gt; -1
  </code></pre>
  
  <p>this error message comes out.</p>
  
  <p>I've checked my resource files several times, and there was no fatal error.
  There are only png icons and xml files.</p>
  
  <p>I don't know what the '-1' means..</p>
  
  <p>And in my main java files, there are 'cannot resolve symbol R' errors.</p>
  
  <p>My app have launched well last night, but when I wake up and run android studio this morning, it failed. </p>
  
  <p>What should I do?</p>
  
  <p>Here is my gradle</p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  
   android {
  compileSdkVersion 24
  buildToolsVersion "24.0.1"
  
  defaultConfig {
      applicationId "com.exapmle.rantalk"
      minSdkVersion 21
      targetSdkVersion 24
      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-v7:24.1.1'
  compile 'com.android.support:design:24.1.1'
  compile 'com.android.support:cardview-v7:24.1.1'
  compile 'com.android.support:recyclerview-v7:24.1.1'
  compile 'com.android.support:support-v4:24.1.1'
  compile 'com.android.support:support-v13:24.1.1'}
  </code></pre>
  
  <p>Here below, I added my entire gradle output, thanks.</p>
  
  <p>Executing tasks: [:app:generateDebugSources, :app:generateDebugAndroidTestSources, :app:mockableAndroidJar, :app:prepareDebugUnitTestDependencies, :app:compileDebugSources, :app:compileDebugAndroidTestSources, :app:compileDebugUnitTestSources]</p>
  
  <p>Configuration on demand is an incubating feature.
  Incremental java compilation is an incubating feature.
  :app:preBuild UP-TO-DATE
  :app:preDebugBuild UP-TO-DATE
  :app:checkDebugManifest
  :app:preReleaseBuild UP-TO-DATE
  :app:prepareComAndroidSupportAnimatedVectorDrawable2411Library UP-TO-DATE
  :app:prepareComAndroidSupportAppcompatV72411Library UP-TO-DATE
  :app:prepareComAndroidSupportCardviewV72411Library UP-TO-DATE
  :app:prepareComAndroidSupportDesign2411Library UP-TO-DATE
  :app:prepareComAndroidSupportRecyclerviewV72411Library UP-TO-DATE
  :app:prepareComAndroidSupportSupportV132411Library UP-TO-DATE
  :app:prepareComAndroidSupportSupportV42411Library UP-TO-DATE
  :app:prepareComAndroidSupportSupportVectorDrawable2411Library UP-TO-DATE
  :app:prepareDebugDependencies
  :app:compileDebugAidl UP-TO-DATE
  :app:compileDebugRenderscript UP-TO-DATE
  :app:generateDebugBuildConfig UP-TO-DATE
  :app:mergeDebugShaders UP-TO-DATE
  :app:compileDebugShaders UP-TO-DATE
  :app:generateDebugAssets UP-TO-DATE
  :app:mergeDebugAssets UP-TO-DATE
  :app:generateDebugResValues UP-TO-DATE
  :app:generateDebugResources UP-TO-DATE
  :app:mergeDebugResources FAILED</p>
  
  <p>FAILURE: Build failed with an exception.</p>
  
  <ul>
  <li><p>What went wrong:
  Execution failed for task ':app:mergeDebugResources'.</p>
  
  <blockquote>
    <p>-1</p>
  </blockquote></li>
  <li><p>Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.</p></li>
  </ul>
  
  <p>BUILD FAILED</p>
  
  <p>Total time: 7.62 secs</p>