If the Java plugin does not appear in the Add-ons Manager, even though Java is installed, try each of the following, one at a time, and then reopen Firefox to see if that resolves the problem:Remove the pluginreg.dat file
If the Java plugin does not appear in the Add-ons Manager, even though Java is installed, try each of the following, one at a time, and then reopen Firefox to see if that resolves the problem:Remove the pluginreg.dat file