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Allow Firefox to use Java 6 plugin?


We have a legacy web based application that is going to take a while to get rid of - it is frozen at Java 6 u13.  We would like to have our end users connect using Firefox instead of IE.  When I attempt to connect to the URL, I get an error from Firefox.

I've included the error.  I have been trying to figure out how to add the Java 6 plugin but have not been able to figure it out.
Avatar of Jo_Wickerman
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Hi yccdadmins,

As per Oracle:


Older versions of the Java Deployment Toolkit (DT) and the Java Plugin have been disabled by Firefox. Some Java versions are flagged by Firefox as 'Add-ons may be causing problems'.

If Firefox thinks an add-on is unsafe and can cause a security risk, it will block it from loading. In case of a soft block Firefox will present a warning message but will allow the user to continue if they wish but with compromised security. In the case of a hard block Firefox will block installation so that the user cannot use this add-on. To resolve this, the user should update to latest version of Java.

I know you didn't want to hear this, sorry :(

Avatar of CEHJ
How did the developers manage to bungle that? I have stuff here written a very long time ago that runs perfectly well on the latest vm.

If you have that malware-vector of an old JRE installed, either run

a. appletviewer (it's an applet)
b. javaws (it's an app)

from the command line
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CEH - bungled for sure.  It is typical in academia.  They love to develope in house.  They become dependent and then....the developers leave.  We're moving off of this but we need it to work for a while longer.  

We worked to ensure security by setting up a single point of controlled and secure access (through RDS) and the app works with IE but we're sick and tired of dealing with all the other issues that come with IE.  Trying to get this to work with Firefox should get IE out of the picture.

I have Java 6 u13 installed on the system where I need it.  I'm not sure what you're telling me to do.  When I go to Add-ons in Firefox, Java 6 does not show up to Activate.

I attempted to use the "Install Add-on from file.." option but I don't know what file to look for.

What will those commands do?
What will those commands do?
Bypass any browser (with luck in the case of applets)

Actually, on reflection, appletviewer needs a JDK installed but you should be able to get one of the same version from the archives

Any chance of my being able to test this code?
I see where my misunderstanding is.  I don't have access to code.  Here is what I have:

- I have a server with Java 6 u13 installed.
- I have end users who use MS RDS to open Firefox and connect to a URL.
- The application that is run uses Java 6 and must have it installed on the server.

I'm looking for a Firefox solution - not a code solution.  I'm attempting to get the Java 6 plugin working with a current version of Firefox.  If that's not possible we can stick to IE but it seems there should be an override and some way to add the plugin.

Make sense?
I'm not advocating a code solution, though it would make things simpler to run the commands i gave you in a batch file (not that that would count as code)
Ok - I misunderstood.  I guess you need to give me a little more detail because I don't understand when I would run those commands.

Employees log on to our Windows RDS server via remote desktop.  Then they click on a Firefox link to a URL that I have placed on their desktop.  When they open the URL they get the error message in the image file I provided.

In this process, where would it be best to run the executables you mentioned?
If i were doing it, i'd supply a small batch file to which a shortcut would be pointed

Is it an application or applet?
Gotcha!  I'll try that and see if it works....
We connect to a URL.  From within that URL we click on a link that runs an applet.  I tried hitting the site with javaws and that did not work - just threw up a brief command prompt window that goes by too fast to read.

I tried using appletview but cannot find that executable anywhere in the Java6 folders?
I think what I really need to focus on is how to get Firefox (latest version) to see Java 1.6 _13 so I can add it to add-ons.

Java 1.6 (6 Update 13) is where we're stuck at for a bit.  It is installed but Firefox is not seeing it.  Seems that there should be a way to make it see the installed version by overriding some security setting etc...
I tried using appletview but cannot find that executable anywhere in the Java6 folders?
As  i mentioned, you need a JDK for that. See above
I believe this question is unanswerable due to the fact that I an unable to make any changes at all to the system.  It is a serious stumbling bock when it comes to troubleshooting. They system is production as we work to replace it.  I can't install jdk or do anything that involve a change to the existing system.

I'm running the current version of Firefox and I installed Java from:


If any of you can help me get Firefox to see the java plugin for this version of Java, or help me manually install it for this version of Firefox I would be incredibly thankful.
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No way to force current versions of Internet Explorer and/or Firefox to use older, unsecured versions of Java was found in a timely manner.  The solution was to replace the legacy application that would not function with current, secure versions of Java.