FULL PRODUCT VERSION :
JRE6u17

ADDITIONAL OS VERSION INFORMATION :
Windows XP, Windows Vista, Windows 7

A DESCRIPTION OF THE PROBLEM :
During an update (family install) within a user session, a dialog normally prompts the user to close IE if the browser is open (it will also ask you to stop the JQS service if it's still running). This is not the case with a completely silent install, ie. no warning dialogs appear. Instead, you will get an incomplete install-no ARP entry, no CPL. What happens is that the older version gets removed-except for %PROGRAMFILES%\Java\JRE6\bin\MSVCR71.dll , which remains 'open'. As the Core.zip expands and begins to install the new files, it encounters the open file MSVCR71.dll and just stops-it doesn't reverse like a normal failed install. So you're left with a partial install.


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
You must have a previous family version installed, eg. JRE6u13. Then, install JRE-6u17windows-i586.exe /s /v "/qn IEXPLORER=1 MOZILLA=1REBOOT=Suppress" while eg. IE is open. Monitor the contents of %PROGRAMFILES%\Java\JRE6\bin.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
On failure, the installation should restore the previous install, or better yet, unlock or open MSVCR71.dll while the browser is open and continue the silent installation.
ACTUAL -
The contents of %PROGRAMFILES%\Java\JRE6\bin gets deleted except for MSVCR71.dll because it is open. As the core.zip expands in alphabetical order, on reaching MSVCR71.dll, the expansion stops completely, so no files n*-z* are installed. No registration occurs, no ARP entry nor is the Java control panel present any more.

REPRODUCIBILITY :
This bug can be reproduced always.

CUSTOMER SUBMITTED WORKAROUND :
Avoid installation during active user sessions where a browser might be open.
If completely silent installs are being done, either use a (Machine) startup script via Group Policy or via the RunOnceEx key (with admins rights to install).