"java.exe" exited with code 2 Xamarin.Android project

Found the answer after about 20 hours of searching in my project.. So here are the steps to resolve the problem "java.exe" exited with code 2

1) Change the MainDexClasses.bat as described in the link:

http://www.jon-douglas.com/2016/09/05/xamarin-android-multidex/

2) Make sure you have enabled Multidex Option in your Android Application! Have a look at the .csprj file if Multidex is set to true (in my case it wasn't even if I enabled Multidex)

3) Add the following part in your AndroidManifest file

<application android:name="android.support.multidex.MultiDexApplication"></application>

This will tell your Android project to actually use the Multidex-Option given.

After a clean and build I was able to run my application as it is.

After finding this question and @Daniel_97s answer I was able to solve this error only by adding multidex to the project without changing MainDexClasses.bat:

1. Check the option in Project Options:

2. Add MultiDexApplication to Android Manifest:

   <application android:name="android.support.multidex.MultiDexApplication"></application>

Note I was getting this error code 2 on Visual Studio for Mac and on Windows the same app was building successfully. (why?)

The solution in my case was to disable the "Sign the .APK file using the following keystore details". Because the keystore location and/or password was incorrect, java.exe exited with code 2.