During install, core.zip is unzipped and logged to %TEMP%\java_install.log.
This is an improvement over previous Error 1722's, but the log is not providing enough information.

The MSI log when created may contain:
MSI (s) (CC:24) [01:37:44:876]: Executing op: ActionStart(Name=unzipcore,Description=Extracting Installer,)
Action 1:37:44: unzipcore. Extracting Installer
MSI (s) (CC:24) [01:37:44:878]: Executing op: CustomActionSchedule(Action=unzipcore,ActionType=3089,Source=C:\Program Files (x86)\Java\jre6\bin\regutils.dll,Target=MSIunzipcore,)
MSI (s) (CC:58) [01:37:44:884]: Invoking remote custom action. DLL: C:\Program Files (x86)\Java\jre6\bin\regutils.dll, Entrypoint: MSIunzipcore
MSI (s) (CC:30) [01:37:44:884]: Generating random cookie.
MSI (s) (CC:30) [01:37:44:892]: Created Custom Action Server with PID 4060 (0xFDC).
MSI (s) (CC:8C) [01:37:44:935]: Running as a service.
MSI (s) (CC:8C) [01:37:44:938]: Hello, I'm your 32bit Elevated custom action server.
Error 25099.  Unzipping core files failed.
MSI (s) (CC!C0) [01:37:58:472]: Product: Java(TM) 6 Update 12 -- Error 25099.  Unzipping core files failed.

Action ended 1:37:58: InstallFinalize. Return value 3.


%TEMP%\java_install.log contains:
cmdline = "C:\Program Files (x86)\Java\jre6\core.zip" "C:\Program Files (x86)\Java\jre6\" "C:\Users\ADMINI~1\AppData\Local\Temp\java_install.log"
Archive: C:\Program Files (x86)\Java\jre6\core.zip
  extracting: COPYRIGHT
  extracting: LICENSE
  extracting: LICENSE.rtf
  extracting: LICENSE_de.rtf
  extracting: LICENSE_es.rtf
  extracting: LICENSE_fr.rtf
  extracting: LICENSE_it.rtf
  extracting: LICENSE_ja.rtf
  extracting: LICENSE_ko.rtf
  extracting: LICENSE_sv.rtf
  extracting: LICENSE_zh_CN.rtf
  extracting: LICENSE_zh_TW.rtf
  extracting: README.txt
  extracting: THIRDPARTYLICENSEREADME.txt
  extracting: Welcome.html
  extracting: bin/
  extracting: bin/awt.dll
  extracting: bin/axbridge.dll
  extracting: bin/client/
  extracting: bin/client/jvm.dll
  extracting: bin/client/Xusage.txt
  extracting: bin/cmm.dll
  extracting: bin/dcpr.dll
  extracting: bin/deploy.dll
  extracting: bin/deploytk.dll
  extracting: bin/dt_shmem.dll
  extracting: bin/dt_socket.dll
  extracting: bin/eula.dll
  extracting: bin/fontmanager.dll
  extracting: bin/hpi.dll
  extracting: bin/hprof.dll
  extracting: bin/instrument.dll
  extracting: bin/ioser12.dll
  extracting: bin/j2pcsc.dll
  extracting: bin/j2pkcs11.dll
  extracting: bin/jaas_nt.dll
  extracting: bin/java-rmi.exe
  extracting: bin/java.dll
  extracting: bin/java.exe
  extracting: bin/javacpl.cpl
  extracting: bin/javacpl.exe
  extracting: bin/javaw.exe
  extracting: bin/javaws.exe
  extracting: bin/java_crw_demo.dll
  extracting: bin/jawt.dll
  extracting: bin/jbroker.exe
  extracting: bin/JdbcOdbc.dll
  extracting: bin/jdwp.dll
  extracting: bin/jkernel.dll
  extracting: bin/jli.dll
  extracting: bin/jp2iexp.dll
  extracting: bin/jp2launcher.exe
  extracting: bin/jp2native.dll
  extracting: bin/jp2ssv.dll
  extracting: bin/jpeg.dll
  extracting: bin/jpicom.dll
  extracting: bin/jpiexp.dll
  extracting: bin/jpinscp.dll
  extracting: bin/jpioji.dll
  extracting: bin/jpishare.dll
  extracting: bin/jqs.exe
  extracting: bin/jqsnotify.exe
  extracting: bin/jsound.dll
  extracting: bin/jsoundds.dll
  extracting: bin/jucheck.exe
  extracting: bin/jureg.exe
  extracting: bin/jusched.exe
  extracting: bin/keytool.exe
  extracting: bin/kinit.exe
  extracting: bin/klist.exe
  extracting: bin/ktab.exe
  extracting: bin/management.dll
  extracting: bin/mlib_image.dll
  extracting: bin/msvcr71.dllError:fopen: while opening file <bin/msvcr71.dll>

Why couldn't bin/msvcr71.dll be opened?