Problems installing XamarinInstaller.exe
<p>Previously, Xamarin has been working for me on Windows 10 Version 1511, but then I updated to Windows 10 1607 and Visual Studio kept warning me that there is an update, saying "Xamarin for Visual Studio Update Available."  I kept clicking on that, but nothing happened, so finally, I went to Tools -> "Extensions and Updates" and searched for Xamarin, where I downloaded and ran XamarinInstaller.exe.  The problem is that my internet cut out part way through so the installation didn't complete, so now when I try to run a Xamarin.Android project, I get this error:</p>

<pre><code>...
1&gt;Skipping target "_CompileJava" because all output files are up-to-date with respect to the input files.
1&gt;Skipping target "_CreateAdditionalResourceCache" because it has no outputs.
1&gt;C:\Program Files (x86)\Java\jdk1.7.0_55\\bin\java.exe -jar "C:\Program Files (x86)\Android\android-sdk\build-tools\24.0.1\\lib\dx.jar" --no-strict --dex --output=obj\Debug\android\bin obj\Debug\android\bin\classes "C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\MonoAndroid\v4.4\mono.android.jar" 
1&gt;java.lang.UnsupportedClassVersionError: com/android/dx/command/Main : Unsupported major.minor version 52.0
1&gt;  at java.lang.ClassLoader.defineClass1(Native Method)
1&gt;  at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
1&gt;  at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
1&gt;  at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
1&gt;  at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
1&gt;  at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
1&gt;  at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
1&gt;  at java.security.AccessController.doPrivileged(Native Method)
1&gt;  at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
1&gt;  at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
1&gt;  at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
1&gt;  at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
1&gt;  at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:482)
1&gt;Exception in thread "main" 
1&gt;java.lang.UnsupportedClassVersionError: com/android/dx/command/Main  :  Unsupported major.minor version 52.0
1&gt;Done building project "MyProject.Droid.csproj" -- FAILED.
1&gt;Build FAILED.
1&gt;
========== Deploy: 0 succeeded, 1 failed, 0 skipped ==========
</code></pre>

<p>I updated my java from (see <a href="https://stackoverflow.com/questions/6494567/android-ndk-your-app-build-script-points-to-an-unknown-file">Android NDK: Your APP_BUILD_SCRIPT points to an unknown file</a>):</p>

<pre><code>C:\Program Files (x86)\Java\jdk1.7.0_55
</code></pre>

<p>To,</p>

<pre><code>C:\Program Files\Java\jdk1.7.0_79
</code></pre>

<p>Which fixed the following error,</p>

<pre><code>Severity    Code    Description Project File    Line    Suppression State
Error       java.lang.UnsupportedClassVersionError: com/android/dx/command/Main  :  Unsupported major.minor version 52.0    TuberEduMobile.Droid    C:\Program Files (x86)\MSBuild\Xamarin\Android\Xamarin.Android.Common.targets   2159
</code></pre>

<p>But that did not resolve the first issue above.  Also, I downloaded android-ndk-r12b, but when I attempt to build using <code>ndk-build</code>, I get this error:</p>

<pre><code>Android NDK: Your APP_BUILD_SCRIPT points to an unknown file: C:\projects\android-ndk-r12b/jni/Android.mk
C:/projects/android-ndk-r12b/build//../build/core/add-application.mk:198: *** Android NDK: Aborting...    .  Stop.
</code></pre>

<p>Does anyone have any suggestions?  How can I get my Xamarin.Android working again?  TIA.</p>

<p><strong>UPDATE:</strong></p>

<p>Thank you for the suggestion, @Alan Clark.  Tried uninstalling using the link you indicated and reinstalling Xamarin using <code>XamarinInstaller.exe</code>, and even deleted the old Java <code>jdk1.7.0_55</code> from my machine, where even if I go to <code>Options -&gt; Xamarin -&gt; Android Settings</code> it says for Java Development Kit Location:  </p>

<pre><code>C:\Program Files\Java\Jdk1.7.0_79
</code></pre>

<p>but for some reason it is still pointing at that directory old directory, because I am getting this error when I attempt to build my Xamarin.Android solution:</p>

<pre><code>1&gt;C:\Program Files (x86)\MSBuild\Xamarin\Android\Xamarin.Android.Common.targets(2159,3): error MSB6004: The specified task executable location "C:\Program Files (x86)\Java\jdk1.7.0_55\\bin\java.exe" is invalid.
</code></pre>

<p>Please note that it is pointing to this NDK:</p>

<pre><code>C:\Program Files\Android\ndk\android-ndk\r11c
</code></pre>

<p>Not sure if it is related to my specific problem.</p>

<p>Does anyone have any suggestions?  TIA.</p>