title: Xamarin android emulator error: App not installed
body: <p>I am trying to install app on a Nexus 4 virtual android 5.1 on Xamarin Virtual machine. If i want to install an app, I mostly get this error: App not installed  (don't get this during some installations but 95% get this error).</p>
  
  <p>I did ofcourse lots of research and testing.</p>
  
  <ul>
  <li>Install Android studio their VM. Same error.</li>
  <li><p>found some potential solution <a href="http://mobilityarena.com/fix-application-not-installed-error-androids/" rel="nofollow">here</a></p>
  
  <p>*Reboot the phone: In times like this, first thing to do is to reboot your                  device. Or just shut down, remove and reinsert your battery. <strong>Done and no luck</strong></p>
  
  <p>*Make sure to uninstall any apps you don’t use to free up space, also uninstall previous versions of the same app currently installed on your device.
  <strong>I download them all for the first time via APKpure.com</strong></p>
  
  <p>*Double check the apk files you download and be sure they were completely copied or downloaded. <strong>App are released by companies their self and are fully downloaded</strong></p>
  
  <p>*Try resetting app permissions by going to Settings >Apps>All>Menu key >Reset application permissions or Reset app preferences. <strong>Done and no luck</strong></p>
  
  <p>*Change app installation location to Automatic or Let system decide. <strong>don't know how this is possible without a root</strong></p>
  
  <p>*Make sure your SD card is not mounted or connected to a PC or elsewhere. <strong>no Sd card</strong></p>
  
  <p>*For worst case scenarios, format your SD card – copy it’s contents somewhere else for backup and format. <strong>no Sd card</strong></p>
  
  <p>*The last solution would be to totally wipe your device. Either by doing a factory reset under Settings or by doing a full wipe in recovery mode. <strong>I even reinstalled Xamarin</strong></p></li>
  <li><p>Downloaded an android 4 version, no luck.</p></li>
  <li>I found lots of post where they were talking about signing. I did not change the APK files and I never managed to install them before.</li>
  <li>downloaded never Nexus device with A5.1 and still same error.</li>
  </ul>
  
  <p>Help is much appriciated. </p>