title: Mono.AndroidTools.InstallFailedException: Failure
body: <p>I have run into this issue and my app wont compile. I was trying to use play services in my app but it was giving me resource not found error I got frustrated and removed all the xamarin files and reinstalled everything. that issue went away now this error has popped up. Any help will be appreciated. P.S I am a beginner in android developer. I have copied some parts of the error below: </p>
  
  <pre><code>2&gt;C:\Program Files\Java\jdk1.8.0_91\\bin\keytool.exe -list -alias androiddebugkey -storepass android -keypass android -keystore "C:\Users\xxxx\AppData\Local\Xamarin\Mono for Android\debug.keystore" 
  2&gt;C:\Program Files\Java\jdk1.8.0_91\\bin\jarsigner.exe -keystore "C:\Users\xxxx\AppData\Local\Xamarin\Mono for Android\debug.keystore" -storepass android -keypass android -digestalg SHA1 -sigalg md5withRSA -signedjar bin\Debug\\Messenger.Messenger-Signed-Unaligned.apk C:\Users\xxxx\Desktop\projects\test\Messenger\Messenger\obj\Debug\android\bin\Messenger.Messenger.apk androiddebugkey 
  2&gt;No -tsa or -tsacert is provided and this jar is not timestamped. Without a timestamp, users may not be able to validate this jar after the signer certificate's expiration date (2046-08-06) or after any future revocation date.
  2&gt;C:\Users\xxxx\AppData\Local\Android\android-sdk\build-tools\24.0.1\zipalign.exe 4 "C:\Users\xxxx\Desktop\projects\test\Messenger\Messenger\bin\Debug\Messenger.Messenger-Signed-Unaligned.apk" "bin\Debug\\Messenger.Messenger-Signed.apk" 
  2&gt;:Deployment failed
  2&gt;Mono.AndroidTools.InstallFailedException: Failure [INSTALL_FAILED_UPDATE_INCOMPATIBLE]
  2&gt;   at Mono.AndroidTools.Internal.AdbOutputParsing.Che`enter code here`ckInstallSuccess(String output, String packageName)
  2&gt;   at Mono.AndroidTools.AndroidDevice.&lt;InstallPackage&gt;c__AnonStoreyE.&lt;&gt;m__0(Task`1 t)
  2&gt;   at System.Threading.Tasks.ContinuationTaskFromResultTask`1.InnerInvoke()
  2&gt;   at System.Threading.Tasks.Task.Execute()
  2&gt;The "InstallPackageAssemblies" task failed unexpectedly.
  2&gt;System.AggregateException: One or more errors occurred. ---&gt; Xamarin.AndroidTools.AndroidDeploymentException: InternalError ---&gt; Mono.AndroidTools.InstallFailedException: Failure [INSTALL_FAILED_UPDATE_INCOMPATIBLE]
  2&gt;   at Mono.AndroidTools.Internal.AdbOutputParsing.CheckInstallSuccess(String output, String packageName)
  2&gt;   at Mono.AndroidTools.AndroidDevice.&lt;InstallPackage&gt;c__AnonStoreyE.&lt;&gt;m__0(Task`1 t)
  2&gt;   at System.Threading.Tasks.ContinuationTaskFromResultTask`1.InnerInvoke()
  2&gt;   at System.Threading.Tasks.Task.Execute()
  2&gt;   --- End of inner exception stack trace ---
  2&gt;   at Xamarin.AndroidTools.AndroidDeploySession.&lt;RunLoggedAsync&gt;c__async1.MoveNext()
  2&gt;--- End of stack trace from previous location where exception was thrown ---
  2&gt;   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
  2&gt;   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
  2&gt;   at Xamarin.AndroidTools.AndroidDeploySession.&lt;StartAsync&gt;c__async0.MoveNext()
  2&gt;   --- End of inner exception stack trace ---
  2&gt;   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
  2&gt;   at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
  2&gt;   at System.Threading.Tasks.Task.Wait()
  2&gt;   at Xamarin.Android.Tasks.InstallPackageAssemblies.Execute()
  2&gt;   at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute()
  2&gt;   at Microsoft.Build.BackEnd.TaskBuilder.&lt;ExecuteInstantiatedTask&gt;d__26.MoveNext()
  2&gt;---&gt; (Inner Exception #0) Xamarin.AndroidTools.AndroidDeploymentException: InternalError ---&gt; Mono.AndroidTools.InstallFailedException: Failure [INSTALL_FAILED_UPDATE_INCOMPATIBLE]
  2&gt;   at Mono.AndroidTools.Internal.AdbOutputParsing.CheckInstallSuccess(String output, String packageName)
  2&gt;   at Mono.AndroidTools.AndroidDevice.&lt;InstallPackage&gt;c__AnonStoreyE.&lt;&gt;m__0(Task`1 t)
  2&gt;   at System.Threading.Tasks.ContinuationTaskFromResultTask`1.InnerInvoke()
  2&gt;   at System.Threading.Tasks.Task.Execute()
  2&gt;   --- End of inner exception stack trace ---
  2&gt;   at Xamarin.AndroidTools.AndroidDeploySession.&lt;RunLoggedAsync&gt;c__async1.MoveNext()
  2&gt;--- End of stack trace from previous location where exception was thrown ---
  2&gt;   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
  2&gt;   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
  2&gt;   at Xamarin.AndroidTools.AndroidDeploySession.&lt;StartAsync&gt;c__async0.MoveNext()&lt;---
  2&gt;
  2&gt;Build FAILED.
  2&gt;
  </code></pre>