Java Console Is Incompatible With Firefox 6

After updating Firefox you may receive one (or more) messages stating that Java Console Is Incompatible With Firefox. This article applies equally to Firefox 7 and Firefox 8, even if you install the latest version of Java (currently v6 update 29). The reason is that Oracle have only certified Java Console for Firefox 5 and are not pushing updates quickly enough to keep up with the Firefox rapid release schedule.

Expect this issue to continue in future Firefox versions unless Oracle start updating Java more quickly… The error  occurs when you update Firefox, after Firefox restarts you see the “Java Console Is Incompatible With Firefox” message.

Java Console is an add-on in Firefox installed by Oracle’s popular Java program. If you have several old versions of it installed on your computer then you will also have several versions of the Java Console add-on in Firefox – you will receive the ‘Java Console Is Incompatible With Firefox 6.0’ error message for each and every version of the Java Console add-on in Firefox.

Is There A New Version? No. Checking Firefox add-ons for updates will not find any newer version of Java Console that is compatible with Firefox 6.0

Does It Matter?

  • No – unless you are a developer or have a specialized requirement you can safely ignore these incompatible Java Console add-ons errors. The Java Console is mostly a redundant add-on i.e. it is not needed for Java itself to work in Firefox.
  • There is no performance loss in having these add-ons as disabled.
  • You can test that Java still works properly in Firefox 6.0 by visiting Oracle’s test page here. If you have an old version it is worth updating it for general security and stability but it will not resolve the Console error message.

Warning: If you do have multiple versions of it installed on your computer, this is a security risk as malware will use (attack) your oldest version which will have security holes subsequently fixed by later versions.

You should uninstall all old versions of Java (via Add/Remove Programs or Program Features) and ensure that you have installed the latest version for best security – Oracle’s test page (see link above) will tell you if you have the latest version or not.

8 Responses to: "Java Console Is Incompatible With Firefox 6"

  1. xbbdc says:

    i currently have java 6 update 6 and it does not work with firefox 6.

    • admin says:

      Your issue is not a Firefox 6 or Java Console issue – Java Console is NOT Java.

      But hey, we’re nice guys so we’ll try to help you anyway :-) The reason Java does not work for YOU is that your Java 6 update 6 is more than 3 years out of date.

      From Oracle’s Java website: “Starting with Firefox 3.6, Java-based applications will NOT work unless you are running Java version 6 Update 10 or newer”. So your Java would never have worked in Firefox 3.6 or 4 or 5 either…

      Please follow the link in our article to Oracle’s Java test page and install the latest version – Java 6 update 26. Then uninstall ALL your older versions of Java and you should be ok

  2. Joe90 says:

    thnaks for the advice, i have 6 update 26 and was scratching my head why this incompatable message appeared as java itself works fine. Wonder why firefox doesn’t just hide it rather than worry people for no reason…

  3. Stefan says:

    “Oracle’s Java program (used by most websites)”

    Er, I don’t know what websites you visit, but there are actually only a few that use Java.

    The only ones I know are a broadband speed tester and

    • admin says:

      Hi Stefan, thanks for your comment.

      Java is still required by many online games (e.g. Runescape), applications (e.g. web calculators) and corporate websites – as well as offline applications such as Open Office.

      However, we do take your point about ‘most’ – we can’t find reliable stats for website Java usage so perhaps we should have said ‘used by most people’ – 80% of our visitors have Java installed and that proportion is similar to that of customers in our computer repair business.

      • Bryan says:

        I need to remote to company’s server from time to time.
        I don’t have Jave console, then I cannot use or install Juniper SSL vpn. then I cannot remote to company’s server any more.
        This issue is shutting me out of firefox.
        I hope Mozilla can solve this along with Oracle.

  4. mat says:

    Java 6 Update 27 is out and the console is still not recognized

    • admin says:

      Noticed that today – ironically, looking at the release notes for the new update 27, Oracle released it to make Java certified for FF5! Not good for a company of Oracle’s size – by the time they certify FF6 Firefox might be up to version 7 or 8…