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Can't get Firefox to "downgrade" Java JRE version
I recently allowed the Java updater to update my Java JRE from 1.6.x to 1.7.x. However I have a critical web site that will not run the applet unless it sees a 1.6x "only" JRE. (yes, it is a dumb site) . Anyway, I removed the 1.7 version, and re-installed 1.6 but Firefox still shows the 1.7 version in my add-ons and I can't remove the references or get them to update to 1.6x. I still can't get the web site to launch the applet that I need from FF because it thinks I am not running 1.6x. I am NOT having this problem using IE8.. it seems to have downgraded just fine.
Krejt Përgjigjet (4)
Hi,
You can try deleting the pluginreg.dat file in the Firefox Profile Folder after exiting Firefox. You can also open the profile folder via Firefox Help (Alt + H) > Troubleshooting Information > Show Folder. Please note that versions below 1.6.33 usually would be automatically blocked by Firefox because of severe vulnerabilities.
I'm not entirely sure what is happening (or how), but when I attempt to delete (or modify) the pluginreg.dat file and then reopen Firefox. The file gets regenerated.
I'm not entirely sure what is happening (or how), but when I attempt to delete (or modify) the pluginreg.dat file and then reopen Firefox. The file gets regenerated.
You can see the installed plugins that are enabled on the about:plugins page.
You can set the plugin.expose_full_path pref to true on the about:config page to see the full path of plugins on the about:plugins page.
It is best not to leave that pref set to true as it exposes that full path to web servers, so reset that pref to false after you are done with the about:plugins page.
See "Manually uninstalling a plugin":