Error building Player: Win32Exception: (when building an android .apk)

this is the full error:

Error building Player: Win32Exception: ApplicationName=‘javac.exe’, CommandLine=‘-bootclasspath “D:/Programs/DevelopmentTools/adt-bundle-windows-x86_64-20131030/sdk/platforms/android-22\android.jar” -d “D:\UnityProjects\unititled-digital-tcg\Temp\StagingArea\bin\classes” -source 1.6 -target 1.6 -encoding UTF-8 “com~our company~~our game~\R.java” “com\google\android\gms\R.java” “com\google\example\games\mainlibproj\R.java”’, CurrentDirectory=‘D:\UnityProjects\unititled-digital-tcg\Temp\StagingArea\gen’

we just installed google play services plugin

I think this question was asked numerous times.

You have JRE installed, while you need JDK to build in Unity. Please download and install JDK from Oracle website.

BTW I fixed that for Unity 5 - the message should say “you have JDK missing, please install it”.