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.
Upgrading to the latest Java 7 version should resolve the issue. If you see the warning message, follow these steps:
This could be due to a conflict that Java versions 7u10 and above have with stand alone installations of JavaFX. Example: If Java 7u5 and JavaFX 2.1.1 are installed and if Java is updated, Firefox is unable to detect that the newly installed Java.
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