Have you tried reinstalling Java to your computer?
If not, please do so.

Does Java content run on Firefox?
You can test Java here.

Please report back soon.

Yes, I have reinstalled Java several times. I have closed / open browser too. As for Test Java - it says unable to verify Java installed on this computer.

Please try running the Java test on another internet browser (not Google Chrome).

Java test didn't work on Firefox or IE. I went through everything in the Troublshooter. Still didn't work. Manually deleted all versions of Java. Rebooted the computer and reinstalled Java. Closed and Opened Firefox. Re-tesdted Java - still doesn't work.

Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.

You can try these free programs to scan for malware, which work with your existing antivirus software:

• Microsoft Safety Scanner
• MalwareBytes' Anti-Malware
• TDSSKiller - AntiRootkit Utility
• Hitman Pro
• ESET Online Scanner

Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista/XP if you don't already have one.

Further information can be found in the Troubleshoot Firefox issues caused by malware article.

Did this fix your problems? Please report back soon.

There is a setting in the Java applet in the Windows Control Panel to prevent Java from running in your browsers. It seems unlikely this would have been turned on by accident, but if you are in a managed environment, it's possible it's an IT setting. You could check just in case.

Windows Control Panel > Java (32-bit)

(If you view your CP by category, check Programs)

Then visit the Security tab (screen shot attached).

Also, please try scanning for registry errors after you uninstall all of the Java programs. This can be done using CCleaner.

Also ensure that you remove all Java application data and the program directory from your computer's hard drive before reinstalling it.

WARNING: Removing folders/files can cause damage to other programs and the Windows operating system. use caution when manually deleting folders/files. Creating a backup of any deleted files is highly recommended!

After the re-install, I checked the Java control panel - security tab and the box to enable java on browser was un-checked (maybe default with install) Anyway, it works now. Thanks for your help, I couldn't have done it without you.

We are glad to hear that your Firefox issue has been resolved.
Please don't forget to mark jscher2000's answer as the solution. This will help other users find the answer to their problem faster.

We hope that you will continue browsing with us here on Mozilla Firefox.
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