Java plug-in does not work in Firefox after installing Java 7 Update 10 (7u10) and above.
This article applies to:
Upon completing install of Java 7u10 and above, following error appears:
Error: A plug-in is needed to display this content. Install Plugin
This is due, as we have seen, to a conflict that Java 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 to 7u10, Firefox is unable to detect that Java 7u10 is installed.
To resolve this issue it is recommended to uninstall all versions of Java and JavaFX before installing Java 7u10 and above.
Please follow the steps below for resolving this issue.