
( explains why "rejected" plugins are entered in the section of pluginreg.dat in case it helps.) I don't know why Firefox is seeing your ugin as invalid. If no one here has any other ideas, you can also consider filing a new bug on or ask over in where there are other Mac users with the latest Java and Firefox, who may be able to help. Mac + firefox + java applet plugins = pain Long shot but maybe something in this MozillaZine forum thread will help: See Profile Manager - Create, remove or switch Firefox profiles.

To rule out Firefox profile issues (user data and settings) you can try creating a new, additional Firefox profile for testing purposes.

by deleting the /Library/Internet Plug-Ins/ugin file? Ref: You did say you deleted the Java plugin before reinstalling Java. ( Bug 616271 - Plugin-like files add overhead on every startup explains why "rejected" plugins are entered in the section of pluginreg.dat in case it helps.) I could try downloading Java 7 again in case there's an error in the install file, but that seems unlikely, since Java installation proceeded without error. Do you want a list of the contents (from ls -l)? I don't think that could be the problem if the Java plugin itself is listed as invalid.

I looked into the plugin directory but I wouldn't know what might conflict. Why would the plugin be considered invalid? POSSIBLE CLUE: the Java plugin is listed in the "" section of that file. I deleted pluginreg.dat and restarted Firefox, no help. Every one of the testers you asked if I tried says Java is either blocked or not installed.) "Enable Java content in the browser" is checked in the security tab of the Java control panel. I entered the command to refresh the blocklist, but that didn't help because there's no plugin to unblock. Firefox doesn't find it, so I can't enable it. The Java plugin doesn't show in Tools > Add-ons > Plugins.
