title: Android Studio Error: Execution failed for task ':app:processDebugManifest'
body: <p>I am completely new to Android Studio so it may sound a silly thing to an experienced person.</p>
  
  <p>I am getting an error in Android Studio which states:</p>
  
  <pre><code>Error:Execution failed for task ':app:processDebugManifest'.
  &gt; Manifest merger failed : Attribute meta-data#android.support.VERSION@value 
  value=(25.3.1) from [com.android.support:design:25.3.1] 
  AndroidManifest.xml:27:9-31
  is also present at [com.android.support:appcompat-v7:26.0.0-alpha1] 
  AndroidManifest.xml:27:9-38 value=(26.0.0-alpha1).
  Suggestion: add 'tools:replace="android:value"' to &lt;meta-data&gt; element at 
  AndroidManifest.xml:25:5-27:34 to override.
  </code></pre>
  
  <p>I have Googled this and tried looking into it to solve it on my own, however, similar issues that I have found aren't quite the same errors.</p>
  
  <p>I'm not experienced enough to understand and generate a fix for it although I understand some of it.</p>
  
  <p>It may be the case that I need to provide more information for this so please let me know if so. </p>
  
  <p><em>EDIT</em>:</p>
  
  <p><strong>AndroidManifest.xml</strong>:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.g732d.appname"
      &gt;
  
      &lt;application
          android:allowBackup="true"
          android:icon="@mipmap/ic_launcher"
          android:label="@string/app_name"
          android:roundIcon="@mipmap/ic_launcher_round"
          android:supportsRtl="true"
          android:theme="@style/AppTheme"&gt;
  
          &lt;activity
              android:name=".HomeActivity"
              android:label="@string/app_name"&gt;
              &lt;intent-filter&gt;
                  &lt;action android:name="android.intent.action.MAIN" /&gt;
  
                  &lt;category android:name="android.intent.category.LAUNCHER" /&gt;
              &lt;/intent-filter&gt;
          &lt;/activity&gt;
  
          &lt;activity android:name=".Patients" /&gt;
  
          &lt;activity android:name=".NewPatient" /&gt;
  
          &lt;activity android:name=".StartActivity"&gt;&lt;/activity&gt;
  
      &lt;/application&gt;
  
  &lt;/manifest&gt;
  </code></pre>
  
  <p><strong>build.gradle (Project: appname)</strong>:</p>
  
  <pre><code>// Top-level build file where you can add configuration options common to 
  all sub-projects/modules.
  
  buildscript {
      repositories {
          jcenter()
      }
      dependencies {
          classpath 'com.android.tools.build:gradle:2.3.3'
  
          // NOTE: Do not place your application dependencies here; they 
  belong
          // in the individual module build.gradle files
      }
  }
  
  allprojects {
      repositories {
          jcenter()
          maven {
              url "https://maven.google.com"
          }
      }
  }
  
  task clean(type: Delete) {
      delete rootProject.buildDir
  }
  </code></pre>
  
  <p><strong>build.gradle (Module: App)</strong>:</p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 26
      buildToolsVersion "26.0.0"
      defaultConfig {
          applicationId "com.g732d.appname"
          minSdkVersion 19
          targetSdkVersion 26
          versionCode 1
          versionName "1.0"
          testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
      }
      buildTypes {
          release {
              minifyEnabled false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
          }
      }
  }
  
  dependencies {
      compile fileTree(dir: 'libs', include: ['*.jar'])
      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.constraint:constraint-layout:1.0.2'
      testCompile 'junit:junit:4.12'
      compile 'com.android.support:design:25.3.1'
      compile 'com.google.android.gms:play-services-ads:11.0.1'
      compile 'com.google.android.gms:play-services-maps:11.0.1'
  }
  </code></pre>
  
  <p><em>SECOND EDIT:</em></p>
  
  <p>Following the answer by Arefeh and the comment by Kunal, I changed the version mismatch by replacing <code>compile 'com.android.support:design:25.3.1'</code> with <code>compile 'com.android.support:design:26.0.0-beta2'</code>.</p>
  
  <p>For this to work, I had to add <code>maven { url "https://maven.google.com" }</code> in the <code>build.gradle (Project: appname)</code> file within <code>allprojects{}</code> (have updated above to illustrate this).</p>
  
  <p>Now I keep getting a render error which says <code>failed to instantiate one or more classes</code>. The classes are different for each activity depending on what I've used in the activity e.g.</p>
  
  <pre><code>The following classes could not be instantiated:
      - android.support.v7.widget.AppCompatImageView
      ...
      ...
  </code></pre>