System Information:
OS with service pack: Microsoft Windows XP Professional 5.1.2600 Service Pack 2 Build 2600
OS Locale:en-us;English (United States)
Browser and version: IE 7.0.5730.11IC, Firefox v2.0.0.11
Pre-installed JRE version: 6u03, 1.4.2_13

Web start failed to launch/trigger Kernel installation as expected even after detecting toolkit plugin as not installed.

Expected Behavior: Click on Launch button should trigger Kernel installation followed by an on-demand installation of additional components for the Java Webstart app

Actual Behavior: Click (even multiple) on Launch button failed to trigger Kernel installation.

Steps to Reproduce:
Exact steps to reproduce failure:
1. Uninstall 6u10 from your system
2. Remove DT plugin from Windows System32 directory: Delete this file: C:\windows\system32\deploytk.dll
3. Remove DT plugin from Firefox plugins directory. Delete this file: C:\Program Files\Mozilla Firefox\plugins\npdeploytk.dll
4. Restart IE and Firefox browsers.
5. Run Web Start Launch Button, min version 1.6.0_10, with kernel <javaws.html>
6. Click on the Launch button. This will trigger a kernel installation
7. When the installation completes, the Java Webstart app will trigger an on-demand installation of additional components
(*Above steps failed to initiate* both in IE7 and Firefox after repeated/several attempts)
*Note: *Default installed version was 6u03
Reinstalled 6u10 using online installer -
http://javadl.sun.com/webapps/download/GetFile/1.6.0_10-ea-b08/windows-i586/jre-6u10-ea-windows-i586-p-iftw.exe

This time the detection happened as normal and Java Webstart app (notepad) triggered an on-demand installation of additional components
8. The Notepad Java WebStart app is shown and the page detected the existence of DT plugin, both in IE7 and Firefox


Other Scenarios:

Installed Version: 1.4.2_13
(Without 6u03 or 6u10)
Results for 3.3:
Test createWebStartLaunchButton using notepad.jnlp (minimum version 1.6.0_10)
Detected that toolkit plugin was not installed
Detected installed version: 1.5.0
Note: Wrong JRE version detected in this phase

Clicked on "Launch" Button - Do you want to run or save this file - Run - Do you want to run this software? - Click Run - Downloading Java Installer - Java Setup - Progress (Installing Java) - You have successfully installed Java (Finish).

IE 7 had message "To help protect your security, IE blocked this site from displaying files to your computer. Click here for options...Clicked and "Download File"

Now the message is:
Test createWebStartLaunchButton using notepad.jnlp (minimum version 1.6.0_10)
Detected that toolkit plugin was installed
Detected installed version: 1.4.2_13
Detected installed version: 1.6.0_10
Clicked Launch button again to initiate "Java web Start Launcher" - Additional Components Needed (Installing Additional Components) - Launched Notepad application and console detected exact Java Web Start 1.6.0_10-ea

2nd Scenario -
Installed JRE version -
java version "1.6.0_03"
Java(TM) SE Runtime Environment (build 1.6.0_03-b05)
Java HotSpot(TM) Client VM (build 1.6.0_03-b05, mixed mode, sharing)

Results for 3.3:
Test createWebStartLaunchButton using notepad.jnlp (minimum version 1.6.0_10)
Detected that toolkit plugin was not installed
Detected installed version: 1.6.0

Clicked on "Launch" button - Downloaded Notepad application with 6u03
Note: Additioal Components Needed action didn't initiate
- Done

Repetitive actions bored same results.

3rd Scenario (Clean System - Without any JRE version installed) -
Results for 3.3:
Test createWebStartLaunchButton using notepad.jnlp (minimum version 1.6.0_10)
Detected that toolkit plugin was not installed

Clicked "Launch" - installation initiated

Test createWebStartLaunchButton using notepad.jnlp (minimum version 1.6.0_10)
Detected that toolkit plugin was installed

Detected installed version: 1.6.0_10
Another click was able to launch Notepad after downloading and Installing "Additional Components Needed"