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When attenption to run a Java (lasted version) app, warning security box appears (no text displayed) and then Firefox is totally locked


Using Vista, Foxfire 18.0.1 runs fine until attempting to access a site that need Java to display information. Now with the recent security warning, I first get a screen that that indicated "This plug in has security vulnerabilities -- Click here to activate Java Platform SE & U Platform."

When I click to activate, another box appears the indicates security warning. Only the box appears and at that point Foxfire is totally locked up. At that point I need to go the Task Master to kill Foxfire as well as the security popup window.

The Java Control Panel indicates that I have the latest version of Java.


Additional System Details

Installed Plug-ins

  • Next Generation Java Plug-in 10.11.2 for Mozilla browsers
  • Shockwave Flash 11.5 r502
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.
  • RealPlayer(tm) LiveConnect-Enabled Plug-In
  • RealPlayer Download Plugin
  • Adobe PDF Plug-In For Firefox and Netscape "9.5.3"
  • RealNetworks(tm) RealDownloader Chrome Background Extension Plug-In
  • RealNetworks(tm) RealDownloader PepperFlashVideoShim Plug-In
  • RealNetworks(tm) RealDownloader HTML5VideoShim Plug-In
  • RealDownloader Plugin
  • 4.1.10329.0
  • npmnqmp 989898989877
  • Windows Presentation Foundation (WPF) plug-in for Mozilla browsers
  • Package Installer & Install Conduit


  • User Agent: Mozilla/5.0 (Windows NT 6.0; WOW64; rv:18.0) Gecko/20100101 Firefox/18.0

More Information

  • Top 25 Contributor
  • Moderator
190 solutions 1961 answers

You can bypass the first Firefox "Click to Play" prompt for trusted sites by setting Firefox to always activate plugins for specific sites - see How to allow Java on trusted sites

The second prompt is from Java itself, since the default security level has been increased to "High" in Java 7 Update 11. Ref:

From the Java 7 Update 11 release notes:

Bug Fixes
This release contains fixes for security vulnerabilities. For more information, see Oracle Security Alert for CVE-2013-0422.
In addition, the following change has been made:
Area: deploy
Synopsis: Default Security Level Setting Changed to High
The default security level for Java applets and web start applications has been increased from "Medium" to "High". This affects the conditions under which unsigned (sandboxed) Java web applications can run. Previously, as long as you had the latest secure Java release installed applets and web start applications would continue to run as always. With the "High" setting the user is always warned before any unsigned application is run to prevent silent exploitation.

It might help if you could post a link to some of the sites where Firefox locks up after you get the second security prompt, so that other users with Java 7 Update 11 can check it out. (I'm using Java 6 Update 38 so I don't get that second Java security prompt)

Modified by AliceWyman

Question owner

I am running Java Platform 7 U 11 Firefox and Java both indicate it is the latest version. The Java plugin has been set to enabled. When in the plugin screen (Accessed by the 'tools' menu tab), I find nothing for doing a process to indicate trusted of sites so I can bypass security question of Firefox. When I click on the "This plug in has security vulnerabilities -- Click here to activate Java Platform SE & U Platform," a blank warming window appears with no text or options to select and at that point Firefox is totally locked. This happen with any site that needs Java to run (e.g., US Gov Aviation Weather) and not one unique site.


KyleR123 0 solutions 1 answers

I had this issue accessing a website internal to our network. Since I obviously trust that website I followed this video and got it working


  • Top 25 Contributor
  • Moderator
190 solutions 1961 answers

HarshSteve, if you get a Java "Security Warning" (shown here) but it doesn't include any text and freezes Firefox, something is definitely wrong.

Try the basic troubleshooting steps to see if you can pin down the problem: Troubleshoot and diagnose Firefox problems